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  • Protein Structure, Tertiary  (236)
  • Nature Publishing Group (NPG)  (236)
  • American Institute of Physics (AIP)
  • 2010-2014  (236)
  • 1990-1994
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  • 1
    Publication Date: 2014-10-09
    Description: The neutralizing antibody response to influenza virus is dominated by antibodies that bind to the globular head of haemagglutinin, which undergoes a continuous antigenic drift, necessitating the re-formulation of influenza vaccines on an annual basis. Recently, several laboratories have described a new class of rare influenza-neutralizing antibodies that target a conserved site in the haemagglutinin stem. Most of these antibodies use the heavy-chain variable region VH1-69 gene, and structural data demonstrate that they bind to the haemagglutinin stem through conserved heavy-chain complementarity determining region (HCDR) residues. However, the VH1-69 antibodies are highly mutated and are produced by some but not all individuals, suggesting that several somatic mutations may be required for their development. To address this, here we characterize 197 anti-stem antibodies from a single donor, reconstruct the developmental pathways of several VH1-69 clones and identify two key elements that are required for the initial development of most VH1-69 antibodies: a polymorphic germline-encoded phenylalanine at position 54 and a conserved tyrosine at position 98 in HCDR3. Strikingly, in most cases a single proline to alanine mutation at position 52a in HCDR2 is sufficient to confer high affinity binding to the selecting H1 antigen, consistent with rapid affinity maturation. Surprisingly, additional favourable mutations continue to accumulate, increasing the breadth of reactivity and making both the initial mutations and phenylalanine at position 54 functionally redundant. These results define VH1-69 allele polymorphism, rearrangement of the VDJ gene segments and single somatic mutations as the three requirements for generating broadly neutralizing VH1-69 antibodies and reveal an unexpected redundancy in the affinity maturation process.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Pappas, Leontios -- Foglierini, Mathilde -- Piccoli, Luca -- Kallewaard, Nicole L -- Turrini, Filippo -- Silacci, Chiara -- Fernandez-Rodriguez, Blanca -- Agatic, Gloria -- Giacchetto-Sasselli, Isabella -- Pellicciotta, Gabriele -- Sallusto, Federica -- Zhu, Qing -- Vicenzi, Elisa -- Corti, Davide -- Lanzavecchia, Antonio -- U19 AI-057266/AI/NIAID NIH HHS/ -- England -- Nature. 2014 Dec 18;516(7531):418-22. doi: 10.1038/nature13764. Epub 2014 Oct 5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Insitute for Research in Biomedicine, Universita della Svizzera Italiana, Via Vincenzo Vela 6, 6500 Bellinzona, Switzerland. ; Department of Infectious Diseases and Vaccines MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland 20878, USA. ; Viral Pathogens and Biosafety Unit, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan, Italy. ; Humabs BioMed SA, Via Mirasole 1, 6500 Bellinzona, Switzerland. ; Unit of Preventive Medicine, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan, Italy. ; 1] Insitute for Research in Biomedicine, Universita della Svizzera Italiana, Via Vincenzo Vela 6, 6500 Bellinzona, Switzerland [2] Humabs BioMed SA, Via Mirasole 1, 6500 Bellinzona, Switzerland [3]. ; 1] Insitute for Research in Biomedicine, Universita della Svizzera Italiana, Via Vincenzo Vela 6, 6500 Bellinzona, Switzerland [2] Insitute for Microbiology, ETH Zurich, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland [3].〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25296253" target="_blank"〉PubMed〈/a〉
    Keywords: Adult ; Amino Acid Sequence ; Antibodies, Neutralizing/*genetics ; Cells, Cultured ; Complementarity Determining Regions/chemistry/*genetics ; Female ; Hemagglutinin Glycoproteins, Influenza Virus/immunology ; Humans ; Immunoglobulin Heavy Chains/genetics ; Influenza, Human/*immunology/virology ; Male ; Middle Aged ; Models, Molecular ; Mutation/*genetics ; Orthomyxoviridae/*immunology/metabolism ; Polymorphism, Genetic ; Protein Binding/genetics ; Protein Structure, Tertiary ; Young Adult
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  • 2
    Publication Date: 2014-12-04
    Description: Ryanodine receptors (RyRs) mediate the rapid release of calcium (Ca(2+)) from intracellular stores into the cytosol, which is essential for numerous cellular functions including excitation-contraction coupling in muscle. Lack of sufficient structural detail has impeded understanding of RyR gating and regulation. Here we report the closed-state structure of the 2.3-megadalton complex of the rabbit skeletal muscle type 1 RyR (RyR1), solved by single-particle electron cryomicroscopy at an overall resolution of 4.8 A. We fitted a polyalanine-level model to all 3,757 ordered residues in each protomer, defining the transmembrane pore in unprecedented detail and placing all cytosolic domains as tertiary folds. The cytosolic assembly is built on an extended alpha-solenoid scaffold connecting key regulatory domains to the pore. The RyR1 pore architecture places it in the six-transmembrane ion channel superfamily. A unique domain inserted between the second and third transmembrane helices interacts intimately with paired EF-hands originating from the alpha-solenoid scaffold, suggesting a mechanism for channel gating by Ca(2+).〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4300236/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4300236/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zalk, Ran -- Clarke, Oliver B -- des Georges, Amedee -- Grassucci, Robert A -- Reiken, Steven -- Mancia, Filippo -- Hendrickson, Wayne A -- Frank, Joachim -- Marks, Andrew R -- P01 HL081172/HL/NHLBI NIH HHS/ -- R01 AR060037/AR/NIAMS NIH HHS/ -- R01 GM029169/GM/NIGMS NIH HHS/ -- R01 HL061503/HL/NHLBI NIH HHS/ -- R01 HL083418/HL/NHLBI NIH HHS/ -- R01AR060037/AR/NIAMS NIH HHS/ -- R01GM29169/GM/NIGMS NIH HHS/ -- R01HL061503/HL/NHLBI NIH HHS/ -- U54GM095315/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2015 Jan 1;517(7532):44-9. doi: 10.1038/nature13950. Epub 2014 Dec 1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology and Cellular Biophysics, Columbia University, New York, New York 10032, USA. ; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA. ; 1] Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA [2] Howard Hughes Medical Institute, Columbia University, New York, New York 10032, USA. ; 1] Department of Physiology and Cellular Biophysics, Columbia University, New York, New York 10032, USA [2] Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA. ; 1] Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA [2] Howard Hughes Medical Institute, Columbia University, New York, New York 10032, USA [3] Department of Biological Sciences, Columbia University, New York, New York 10027, USA. ; 1] Department of Physiology and Cellular Biophysics, Columbia University, New York, New York 10032, USA [2] Department of Medicine, Columbia University, New York, New York 10032, USA [3] Wu Center for Molecular Cardiology, College of Physicians and Surgeons of Columbia University, New York, New York 10032, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25470061" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Calcium/deficiency/metabolism/pharmacology ; Cell Membrane/metabolism ; Cryoelectron Microscopy ; Cytosol/metabolism ; Ion Channel Gating/drug effects ; Muscle, Skeletal/chemistry ; Protein Structure, Tertiary ; Rabbits ; Ryanodine Receptor Calcium Release Channel/*chemistry/metabolism/*ultrastructure ; Tacrolimus Binding Proteins/chemistry/metabolism
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  • 3
    Publication Date: 2014-11-05
    Description: ATP-binding cassette (ABC) transporters translocate substrates across cell membranes, using energy harnessed from ATP binding and hydrolysis at their nucleotide-binding domains. ABC exporters are present both in prokaryotes and eukaryotes, with examples implicated in multidrug resistance of pathogens and cancer cells, as well as in many human diseases. TmrAB is a heterodimeric ABC exporter from the thermophilic Gram-negative eubacterium Thermus thermophilus; it is homologous to various multidrug transporters and contains one degenerate site with a non-catalytic residue next to the Walker B motif. Here we report a subnanometre-resolution structure of detergent-solubilized TmrAB in a nucleotide-free, inward-facing conformation by single-particle electron cryomicroscopy. The reconstructions clearly resolve characteristic features of ABC transporters, including helices in the transmembrane domain and nucleotide-binding domains. A cavity in the transmembrane domain is accessible laterally from the cytoplasmic side of the membrane as well as from the cytoplasm, indicating that the transporter lies in an inward-facing open conformation. The two nucleotide-binding domains remain in contact via their carboxy-terminal helices. Furthermore, comparison between our structure and the crystal structures of other ABC transporters suggests a possible trajectory of conformational changes that involves a sliding and rotating motion between the two nucleotide-binding domains during the transition from the inward-facing to outward-facing conformations.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4372080/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4372080/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kim, JungMin -- Wu, Shenping -- Tomasiak, Thomas M -- Mergel, Claudia -- Winter, Michael B -- Stiller, Sebastian B -- Robles-Colmanares, Yaneth -- Stroud, Robert M -- Tampe, Robert -- Craik, Charles S -- Cheng, Yifan -- 1P41CA196276-01/CA/NCI NIH HHS/ -- P41 CA196276/CA/NCI NIH HHS/ -- P50 GM073210/GM/NIGMS NIH HHS/ -- P50 GM082250/GM/NIGMS NIH HHS/ -- P50GM073210/GM/NIGMS NIH HHS/ -- P50GM082250/GM/NIGMS NIH HHS/ -- R01 GM024485/GM/NIGMS NIH HHS/ -- R01 GM098672/GM/NIGMS NIH HHS/ -- R01GM098672/GM/NIGMS NIH HHS/ -- R37 GM024485/GM/NIGMS NIH HHS/ -- R37GM024485/GM/NIGMS NIH HHS/ -- S10 RR026814/RR/NCRR NIH HHS/ -- S10RR026814/RR/NCRR NIH HHS/ -- England -- Nature. 2015 Jan 15;517(7534):396-400. doi: 10.1038/nature13872. Epub 2014 Nov 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pharmaceutical Chemistry, University of California San Francisco, 600 16th Street, San Francisco, California 94158, USA. ; Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, California 94158, USA. ; Institute of Biochemistry, Biocenter, Goethe-University Frankfurt, Max-von-Laue-Strasse 9, D-60438 Frankfurt am Main, Germany. ; 1] Department of Pharmaceutical Chemistry, University of California San Francisco, 600 16th Street, San Francisco, California 94158, USA [2] Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, California 94158, USA. ; 1] Institute of Biochemistry, Biocenter, Goethe-University Frankfurt, Max-von-Laue-Strasse 9, D-60438 Frankfurt am Main, Germany [2] Cluster of Excellence - Macromolecular Complexes, Goethe-University Frankfurt, Max-von-Laue-Strasse 9, D-60438 Frankfurt am Main, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25363761" target="_blank"〉PubMed〈/a〉
    Keywords: ATP-Binding Cassette Transporters/*chemistry/immunology/*ultrastructure ; Antigens/chemistry/immunology ; Binding Sites ; *Cryoelectron Microscopy ; Crystallography, X-Ray ; Models, Molecular ; Nucleotides/metabolism ; Protein Multimerization ; Protein Structure, Quaternary ; Protein Structure, Tertiary ; Rotation ; Thermus thermophilus/*chemistry
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  • 4
    Publication Date: 2014-11-11
    Description: DNA methylation is an important epigenetic modification that is essential for various developmental processes through regulating gene expression, genomic imprinting, and epigenetic inheritance. Mammalian genomic DNA methylation is established during embryogenesis by de novo DNA methyltransferases, DNMT3A and DNMT3B, and the methylation patterns vary with developmental stages and cell types. DNA methyltransferase 3-like protein (DNMT3L) is a catalytically inactive paralogue of DNMT3 enzymes, which stimulates the enzymatic activity of Dnmt3a. Recent studies have established a connection between DNA methylation and histone modifications, and revealed a histone-guided mechanism for the establishment of DNA methylation. The ATRX-DNMT3-DNMT3L (ADD) domain of Dnmt3a recognizes unmethylated histone H3 (H3K4me0). The histone H3 tail stimulates the enzymatic activity of Dnmt3a in vitro, whereas the molecular mechanism remains elusive. Here we show that DNMT3A exists in an autoinhibitory form and that the histone H3 tail stimulates its activity in a DNMT3L-independent manner. We determine the crystal structures of DNMT3A-DNMT3L (autoinhibitory form) and DNMT3A-DNMT3L-H3 (active form) complexes at 3.82 and 2.90 A resolution, respectively. Structural and biochemical analyses indicate that the ADD domain of DNMT3A interacts with and inhibits enzymatic activity of the catalytic domain (CD) through blocking its DNA-binding affinity. Histone H3 (but not H3K4me3) disrupts ADD-CD interaction, induces a large movement of the ADD domain, and thus releases the autoinhibition of DNMT3A. The finding adds another layer of regulation of DNA methylation to ensure that the enzyme is mainly activated at proper targeting loci when unmethylated H3K4 is present, and strongly supports a negative correlation between H3K4me3 and DNA methylation across the mammalian genome. Our study provides a new insight into an unexpected autoinhibition and histone H3-induced activation of the de novo DNA methyltransferase after its initial genomic positioning.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Guo, Xue -- Wang, Ling -- Li, Jie -- Ding, Zhanyu -- Xiao, Jianxiong -- Yin, Xiaotong -- He, Shuang -- Shi, Pan -- Dong, Liping -- Li, Guohong -- Tian, Changlin -- Wang, Jiawei -- Cong, Yao -- Xu, Yanhui -- England -- Nature. 2015 Jan 29;517(7536):640-4. doi: 10.1038/nature13899. Epub 2014 Nov 10.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Fudan University Shanghai Cancer Center, Institute of Biomedical Sciences, Shanghai Medical College of Fudan University, Shanghai 200032, China [2] State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China. ; Fudan University Shanghai Cancer Center, Institute of Biomedical Sciences, Shanghai Medical College of Fudan University, Shanghai 200032, China. ; National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China. ; 1] High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China [2] National Laboratory for Physical Science at the Microscale, University of Science and Technology of China, Hefei 230026, China [3] School of Life Sciences, University of Science and Technology of China, Hefei 230026, China. ; 1] National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Science, Beijing 100101, China [2] University of Chinese Academy of Science, Beijing 100049, China. ; National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Science, Beijing 100101, China. ; State Key Laboratory of Biomembrane and Membrane Biotechnology, School of Life Sciences, Tsinghua University, Beijing 100084, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25383530" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Catalytic Domain ; Crystallography, X-Ray ; DNA/metabolism ; DNA (Cytosine-5-)-Methyltransferase/*antagonists & ; inhibitors/*chemistry/*metabolism ; DNA Methylation ; Enzyme Activation ; Histones/*chemistry/*metabolism ; Humans ; Mice ; Models, Molecular ; Protein Structure, Tertiary ; Xenopus laevis
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  • 5
    Publication Date: 2014-11-05
    Description: Lantibiotics are a class of peptide antibiotics that contain one or more thioether bonds. The lantibiotic nisin is an antimicrobial peptide that is widely used as a food preservative to combat food-borne pathogens. Nisin contains dehydroalanine and dehydrobutyrine residues that are formed by the dehydration of Ser/Thr by the lantibiotic dehydratase NisB (ref. 2). Recent biochemical studies revealed that NisB glutamylates Ser/Thr side chains as part of the dehydration process. However, the molecular mechanism by which NisB uses glutamate to catalyse dehydration remains unresolved. Here we show that this process involves glutamyl-tRNA(Glu) to activate Ser/Thr residues. In addition, the 2.9-A crystal structure of NisB in complex with its substrate peptide NisA reveals the presence of two separate domains that catalyse the Ser/Thr glutamylation and glutamate elimination steps. The co-crystal structure also provides insights into substrate recognition by lantibiotic dehydratases. Our findings demonstrate an unexpected role for aminoacyl-tRNA in the formation of dehydroamino acids in lantibiotics, and serve as a basis for the functional characterization of the many lantibiotic-like dehydratases involved in the biosynthesis of other classes of natural products.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4430201/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4430201/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ortega, Manuel A -- Hao, Yue -- Zhang, Qi -- Walker, Mark C -- van der Donk, Wilfred A -- Nair, Satish K -- 5T32-GM070421/GM/NIGMS NIH HHS/ -- F32 GM112284/GM/NIGMS NIH HHS/ -- R01 GM 058822/GM/NIGMS NIH HHS/ -- R01 GM058822/GM/NIGMS NIH HHS/ -- R01 GM079038/GM/NIGMS NIH HHS/ -- S10 RR027109 A/RR/NCRR NIH HHS/ -- T32 GM070421/GM/NIGMS NIH HHS/ -- England -- Nature. 2015 Jan 22;517(7535):509-12. doi: 10.1038/nature13888. Epub 2014 Oct 26.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA. ; Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA. ; 1] Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA [2] Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA. ; 1] Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA [2] Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25363770" target="_blank"〉PubMed〈/a〉
    Keywords: Bacterial Proteins/*chemistry/classification/*metabolism ; Bacteriocins/biosynthesis/*metabolism ; Crystallography, X-Ray ; Escherichia coli/genetics ; Glutamic Acid/metabolism ; Hydro-Lyases/*chemistry/classification/*metabolism ; Lactococcus lactis/*enzymology/genetics ; Membrane Proteins/*chemistry/classification/*metabolism ; Models, Molecular ; Nisin/biosynthesis/metabolism ; Phylogeny ; Protein Structure, Tertiary ; RNA, Transfer, Glu/genetics/*metabolism ; Serine/metabolism ; Threonine/metabolism
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  • 6
    Publication Date: 2014-12-05
    Description: Activation of mechanosensitive ion channels by physical force underlies many physiological processes including the sensation of touch, hearing and pain. TRAAK (also known as KCNK4) ion channels are neuronally expressed members of the two-pore domain K(+) (K2P) channel family and are mechanosensitive. They are involved in controlling mechanical and temperature nociception in mice. Mechanosensitivity of TRAAK is mediated directly through the lipid bilayer--it is a membrane-tension-gated channel. However, the molecular mechanism of TRAAK channel gating and mechanosensitivity is unknown. Here we present crystal structures of TRAAK in conductive and non-conductive conformations defined by the presence of permeant ions along the conduction pathway. In the non-conductive state, a lipid acyl chain accesses the channel cavity through a 5 A-wide lateral opening in the membrane inner leaflet and physically blocks ion passage. In the conductive state, rotation of a transmembrane helix (TM4) about a central hinge seals the intramembrane opening, preventing lipid block of the cavity and permitting ion entry. Additional rotation of a membrane interacting TM2-TM3 segment, unique to mechanosensitive K2Ps, against TM4 may further stabilize the conductive conformation. Comparison of the structures reveals a biophysical explanation for TRAAK mechanosensitivity--an expansion in cross-sectional area up to 2.7 nm(2) in the conductive state is expected to create a membrane-tension-dependent energy difference between conformations that promotes force activation. Our results show how tension of the lipid bilayer can be harnessed to control gating and mechanosensitivity of a eukaryotic ion channel.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4682367/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4682367/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Brohawn, Stephen G -- Campbell, Ernest B -- MacKinnon, Roderick -- Howard Hughes Medical Institute/ -- England -- Nature. 2014 Dec 4;516(7529):126-30. doi: 10.1038/nature14013.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Molecular Neurobiology and Biophysics and Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25471887" target="_blank"〉PubMed〈/a〉
    Keywords: Crystallization ; Humans ; Ion Channel Gating/*physiology ; *Models, Molecular ; Mutation ; Oxidation-Reduction ; Potassium Channels/*chemistry/genetics/*metabolism ; Protein Structure, Tertiary
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  • 7
    Publication Date: 2014-03-05
    Description: Antibodies capable of neutralizing HIV-1 often target variable regions 1 and 2 (V1V2) of the HIV-1 envelope, but the mechanism of their elicitation has been unclear. Here we define the developmental pathway by which such antibodies are generated and acquire the requisite molecular characteristics for neutralization. Twelve somatically related neutralizing antibodies (CAP256-VRC26.01-12) were isolated from donor CAP256 (from the Centre for the AIDS Programme of Research in South Africa (CAPRISA)); each antibody contained the protruding tyrosine-sulphated, anionic antigen-binding loop (complementarity-determining region (CDR) H3) characteristic of this category of antibodies. Their unmutated ancestor emerged between weeks 30-38 post-infection with a 35-residue CDR H3, and neutralized the virus that superinfected this individual 15 weeks after initial infection. Improved neutralization breadth and potency occurred by week 59 with modest affinity maturation, and was preceded by extensive diversification of the virus population. HIV-1 V1V2-directed neutralizing antibodies can thus develop relatively rapidly through initial selection of B cells with a long CDR H3, and limited subsequent somatic hypermutation. These data provide important insights relevant to HIV-1 vaccine development.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4395007/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4395007/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Doria-Rose, Nicole A -- Schramm, Chaim A -- Gorman, Jason -- Moore, Penny L -- Bhiman, Jinal N -- DeKosky, Brandon J -- Ernandes, Michael J -- Georgiev, Ivelin S -- Kim, Helen J -- Pancera, Marie -- Staupe, Ryan P -- Altae-Tran, Han R -- Bailer, Robert T -- Crooks, Ema T -- Cupo, Albert -- Druz, Aliaksandr -- Garrett, Nigel J -- Hoi, Kam H -- Kong, Rui -- Louder, Mark K -- Longo, Nancy S -- McKee, Krisha -- Nonyane, Molati -- O'Dell, Sijy -- Roark, Ryan S -- Rudicell, Rebecca S -- Schmidt, Stephen D -- Sheward, Daniel J -- Soto, Cinque -- Wibmer, Constantinos Kurt -- Yang, Yongping -- Zhang, Zhenhai -- NISC Comparative Sequencing Program -- Mullikin, James C -- Binley, James M -- Sanders, Rogier W -- Wilson, Ian A -- Moore, John P -- Ward, Andrew B -- Georgiou, George -- Williamson, Carolyn -- Abdool Karim, Salim S -- Morris, Lynn -- Kwong, Peter D -- Shapiro, Lawrence -- Mascola, John R -- P01 AI082362/AI/NIAID NIH HHS/ -- R01 AI100790/AI/NIAID NIH HHS/ -- UM1 AI100663/AI/NIAID NIH HHS/ -- Intramural NIH HHS/ -- Wellcome Trust/United Kingdom -- England -- Nature. 2014 May 1;509(7498):55-62. doi: 10.1038/nature13036. Epub 2014 Mar 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA [2]. ; 1] Department of Biochemistry, Columbia University, New York, New York 10032, USA [2]. ; 1] Center for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service (NHLS), Johannesburg, 2131, South Africa [2] Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 2050, South Africa [3] Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, 4013, South Africa [4]. ; 1] Center for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service (NHLS), Johannesburg, 2131, South Africa [2] Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 2050, South Africa. ; Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, USA. ; Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. ; 1] Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037, USA [2] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA [3] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA. ; Torrey Pines Institute, San Diego, California 92037, USA. ; Weill Medical College of Cornell University, New York, New York 10065, USA. ; Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, 4013, South Africa. ; Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, USA. ; Center for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service (NHLS), Johannesburg, 2131, South Africa. ; Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and NHLS, Cape Town 7701, South Africa. ; Department of Biochemistry, Columbia University, New York, New York 10032, USA. ; 1] NISC Comparative Sequencing program, National Institutes of Health, Bethesda, Maryland 20892, USA [2] NIH Intramural Sequencing Center, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892, USA. ; Department of Medical Microbiology, Academic Medical Center, Amsterdam 1105 AZ, Netherlands. ; 1] Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037, USA [2] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA [3] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [4] Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA. ; 1] Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, USA [2] Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, USA [3] Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, USA. ; 1] Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, 4013, South Africa [2] Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and NHLS, Cape Town 7701, South Africa. ; 1] Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, 4013, South Africa [2] Department of Epidemiology, Columbia University, New York, New York 10032, USA. ; 1] Center for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service (NHLS), Johannesburg, 2131, South Africa [2] Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 2050, South Africa [3] Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, 4013, South Africa. ; 1] Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA [2] Department of Biochemistry, Columbia University, New York, New York 10032, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24590074" target="_blank"〉PubMed〈/a〉
    Keywords: AIDS Vaccines/chemistry/immunology ; Amino Acid Sequence ; Antibodies, Neutralizing/chemistry/genetics/*immunology/isolation & purification ; Antibody Affinity/genetics/immunology ; Antigens, CD4/immunology/metabolism ; B-Lymphocytes/cytology/immunology/metabolism ; Binding Sites/immunology ; Cell Lineage ; Complementarity Determining Regions/chemistry/genetics/immunology ; Epitope Mapping ; Epitopes, B-Lymphocyte/chemistry/immunology ; Evolution, Molecular ; HIV Antibodies/chemistry/genetics/*immunology/isolation & purification ; HIV Envelope Protein gp160/*chemistry/*immunology ; HIV Infections/immunology ; HIV-1/chemistry/immunology ; Humans ; Models, Molecular ; Molecular Sequence Data ; Neutralization Tests ; Protein Structure, Tertiary ; Somatic Hypermutation, Immunoglobulin/genetics
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  • 8
    Publication Date: 2014-12-05
    Description: NADH oxidation in the respiratory chain is coupled to ion translocation across the membrane to build up an electrochemical gradient. The sodium-translocating NADH:quinone oxidoreductase (Na(+)-NQR), a membrane protein complex widespread among pathogenic bacteria, consists of six subunits, NqrA, B, C, D, E and F. To our knowledge, no structural information on the Na(+)-NQR complex has been available until now. Here we present the crystal structure of the Na(+)-NQR complex at 3.5 A resolution. The arrangement of cofactors both at the cytoplasmic and the periplasmic side of the complex, together with a hitherto unknown iron centre in the midst of the membrane-embedded part, reveals an electron transfer pathway from the NADH-oxidizing cytoplasmic NqrF subunit across the membrane to the periplasmic NqrC, and back to the quinone reduction site on NqrA located in the cytoplasm. A sodium channel was localized in subunit NqrB, which represents the largest membrane subunit of the Na(+)-NQR and is structurally related to urea and ammonia transporters. On the basis of the structure we propose a mechanism of redox-driven Na(+) translocation where the change in redox state of the flavin mononucleotide cofactor in NqrB triggers the transport of Na(+) through the observed channel.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Steuber, Julia -- Vohl, Georg -- Casutt, Marco S -- Vorburger, Thomas -- Diederichs, Kay -- Fritz, Gunter -- England -- Nature. 2014 Dec 4;516(7529):62-7. doi: 10.1038/nature14003.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Microbiology, Garbenstrasse 30, University of Hohenheim, 70599 Stuttgart, Germany. ; 1] Institute for Neuropathology, University of Freiburg, Breisacher Strasse 64, 79106 Freiburg, Germany [2] Hermann-Staudinger-Graduate school, University of Freiburg, Hebelstrasse 27, 79104 Freiburg, Germany. ; Institute for Neuropathology, University of Freiburg, Breisacher Strasse 64, 79106 Freiburg, Germany. ; Department of Biology, University of Konstanz, Universitatsstrasse 10, 78457 Konstanz, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25471880" target="_blank"〉PubMed〈/a〉
    Keywords: Bacterial Proteins/*chemistry ; Binding Sites ; Crystallization ; Crystallography, X-Ray ; Flavoproteins/chemistry ; Iron/chemistry ; *Models, Molecular ; NAD(P)H Dehydrogenase (Quinone)/*chemistry ; Protein Interaction Domains and Motifs ; Protein Structure, Tertiary ; Protein Subunits/chemistry ; Sodium/*chemistry ; Sodium Channels/chemistry ; Vibrio cholerae/*enzymology
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  • 9
    Publication Date: 2014-07-11
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stroebel, David -- Paoletti, Pierre -- England -- Nature. 2014 Jul 10;511(7508):162-3. doi: 10.1038/511162a.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute of Biology, Ecole Normale Superieure, CNRS UMR8197, INSERM U1024, 75005 Paris, France.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25008517" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Humans ; Models, Molecular ; Protein Structure, Tertiary ; Receptors, N-Methyl-D-Aspartate/*chemistry/metabolism/*physiology
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  • 10
    Publication Date: 2014-11-20
    Description: Influenza virus polymerase uses a capped primer, derived by 'cap-snatching' from host pre-messenger RNA, to transcribe its RNA genome into mRNA and a stuttering mechanism to generate the poly(A) tail. By contrast, genome replication is unprimed and generates exact full-length copies of the template. Here we use crystal structures of bat influenza A and human influenza B polymerases (FluA and FluB), bound to the viral RNA promoter, to give mechanistic insight into these distinct processes. In the FluA structure, a loop analogous to the priming loop of flavivirus polymerases suggests that influenza could initiate unprimed template replication by a similar mechanism. Comparing the FluA and FluB structures suggests that cap-snatching involves in situ rotation of the PB2 cap-binding domain to direct the capped primer first towards the endonuclease and then into the polymerase active site. The polymerase probably undergoes considerable conformational changes to convert the observed pre-initiation state into the active initiation and elongation states.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Reich, Stefan -- Guilligay, Delphine -- Pflug, Alexander -- Malet, Helene -- Berger, Imre -- Crepin, Thibaut -- Hart, Darren -- Lunardi, Thomas -- Nanao, Max -- Ruigrok, Rob W H -- Cusack, Stephen -- England -- Nature. 2014 Dec 18;516(7531):361-6. doi: 10.1038/nature14009. Epub 2014 Nov 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble Cedex 9, France [2] University Grenoble Alpes-Centre National de la Recherche Scientifique-EMBL Unit of Virus Host-Cell Interactions, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble Cedex 9, France. ; University Grenoble Alpes-Centre National de la Recherche Scientifique-EMBL Unit of Virus Host-Cell Interactions, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble Cedex 9, France.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25409151" target="_blank"〉PubMed〈/a〉
    Keywords: Catalytic Domain ; Crystallization ; DNA-Directed RNA Polymerases/chemistry/*metabolism ; Gene Expression Regulation, Viral ; Influenza A virus/chemistry/*enzymology ; Influenza B virus/chemistry/*enzymology ; *Models, Molecular ; Promoter Regions, Genetic ; Protein Binding ; Protein Structure, Tertiary ; *RNA Caps/chemistry/metabolism ; RNA, Viral/*biosynthesis/*chemistry ; Virus Replication
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  • 11
    Publication Date: 2014-07-11
    Description: N-methyl-d-aspartate (NMDA) receptors are Hebbian-like coincidence detectors, requiring binding of glycine and glutamate in combination with the relief of voltage-dependent magnesium block to open an ion conductive pore across the membrane bilayer. Despite the importance of the NMDA receptor in the development and function of the brain, a molecular structure of an intact receptor has remained elusive. Here we present X-ray crystal structures of the Xenopus laevis GluN1-GluN2B NMDA receptor with the allosteric inhibitor, Ro25-6981, partial agonists and the ion channel blocker, MK-801. Receptor subunits are arranged in a 1-2-1-2 fashion, demonstrating extensive interactions between the amino-terminal and ligand-binding domains. The transmembrane domains harbour a closed-blocked ion channel, a pyramidal central vestibule lined by residues implicated in binding ion channel blockers and magnesium, and a approximately twofold symmetric arrangement of ion channel pore loops. These structures provide new insights into the architecture, allosteric coupling and ion channel function of NMDA receptors.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4263351/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4263351/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lee, Chia-Hsueh -- Lu, Wei -- Michel, Jennifer Carlisle -- Goehring, April -- Du, Juan -- Song, Xianqiang -- Gouaux, Eric -- R37 NS038631/NS/NINDS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2014 Jul 10;511(7508):191-7. doi: 10.1038/nature13548. Epub 2014 Jun 22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA [2]. ; 1] Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA [2] Howard Hughes Medical Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA. ; Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25008524" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Dizocilpine Maleate/chemistry ; Ion Channels/chemistry ; Ligands ; *Models, Molecular ; Phenols ; Piperidines/chemistry ; Protein Binding ; Protein Structure, Tertiary ; Protein Subunits/chemistry ; Receptors, N-Methyl-D-Aspartate/*chemistry ; Xenopus laevis/*physiology
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  • 12
    Publication Date: 2014-09-12
    Description: To prime reverse transcription, retroviruses require annealing of a transfer RNA molecule to the U5 primer binding site (U5-PBS) region of the viral genome. The residues essential for primer annealing are initially locked in intramolecular interactions; hence, annealing requires the chaperone activity of the retroviral nucleocapsid (NC) protein to facilitate structural rearrangements. Here we show that, unlike classical chaperones, the Moloney murine leukaemia virus NC uses a unique mechanism for remodelling: it specifically targets multiple structured regions in both the U5-PBS and tRNA(Pro) primer that otherwise sequester residues necessary for annealing. This high-specificity and high-affinity binding by NC consequently liberates these sequestered residues--which are exactly complementary--for intermolecular interactions. Furthermore, NC utilizes a step-wise, entropy-driven mechanism to trigger both residue-specific destabilization and residue-specific release. Our structures of NC bound to U5-PBS and tRNA(Pro) reveal the structure-based mechanism for retroviral primer annealing and provide insights as to how ATP-independent chaperones can target specific RNAs amidst the cellular milieu of non-target RNAs.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Miller, Sarah B -- Yildiz, F Zehra -- Lo, Jennifer A -- Wang, Bo -- D'Souza, Victoria M -- England -- Nature. 2014 Nov 27;515(7528):591-5. doi: 10.1038/nature13709. Epub 2014 Sep 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA [2] Department of Biology, Georgetown University, Washington DC 20057, USA. [3]. ; 1] Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA [2]. ; Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25209668" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Cell Line ; Genome, Viral/genetics ; Humans ; *Models, Molecular ; *Moloney murine leukemia virus/chemistry/genetics ; Nuclear Magnetic Resonance, Biomolecular ; *Nucleocapsid Proteins/chemistry/metabolism ; Protein Binding ; Protein Structure, Tertiary ; *RNA, Transfer/chemistry/metabolism ; RNA, Viral/*chemistry/*metabolism ; Reverse Transcription/genetics/*physiology
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  • 13
    Publication Date: 2014-08-15
    Description: The role of long noncoding RNA (lncRNA) in adult hearts is unknown; also unclear is how lncRNA modulates nucleosome remodelling. An estimated 70% of mouse genes undergo antisense transcription, including myosin heavy chain 7 (Myh7), which encodes molecular motor proteins for heart contraction. Here we identify a cluster of lncRNA transcripts from Myh7 loci and demonstrate a new lncRNA-chromatin mechanism for heart failure. In mice, these transcripts, which we named myosin heavy-chain-associated RNA transcripts (Myheart, or Mhrt), are cardiac-specific and abundant in adult hearts. Pathological stress activates the Brg1-Hdac-Parp chromatin repressor complex to inhibit Mhrt transcription in the heart. Such stress-induced Mhrt repression is essential for cardiomyopathy to develop: restoring Mhrt to the pre-stress level protects the heart from hypertrophy and failure. Mhrt antagonizes the function of Brg1, a chromatin-remodelling factor that is activated by stress to trigger aberrant gene expression and cardiac myopathy. Mhrt prevents Brg1 from recognizing its genomic DNA targets, thus inhibiting chromatin targeting and gene regulation by Brg1. It does so by binding to the helicase domain of Brg1, a domain that is crucial for tethering Brg1 to chromatinized DNA targets. Brg1 helicase has dual nucleic-acid-binding specificities: it is capable of binding lncRNA (Mhrt) and chromatinized--but not naked--DNA. This dual-binding feature of helicase enables a competitive inhibition mechanism by which Mhrt sequesters Brg1 from its genomic DNA targets to prevent chromatin remodelling. A Mhrt-Brg1 feedback circuit is thus crucial for heart function. Human MHRT also originates from MYH7 loci and is repressed in various types of myopathic hearts, suggesting a conserved lncRNA mechanism in human cardiomyopathy. Our studies identify a cardioprotective lncRNA, define a new targeting mechanism for ATP-dependent chromatin-remodelling factors, and establish a new paradigm for lncRNA-chromatin interaction.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4184960/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4184960/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Han, Pei -- Li, Wei -- Lin, Chiou-Hong -- Yang, Jin -- Shang, Ching -- Nurnberg, Sylvia T -- Jin, Kevin Kai -- Xu, Weihong -- Lin, Chieh-Yu -- Lin, Chien-Jung -- Xiong, Yiqin -- Chien, Huan-Chieh -- Zhou, Bin -- Ashley, Euan -- Bernstein, Daniel -- Chen, Peng-Sheng -- Chen, Huei-Sheng Vincent -- Quertermous, Thomas -- Chang, Ching-Pin -- HL105194/HL/NHLBI NIH HHS/ -- HL109512/HL/NHLBI NIH HHS/ -- HL111770/HL/NHLBI NIH HHS/ -- HL116997/HL/NHLBI NIH HHS/ -- HL118087/HL/NHLBI NIH HHS/ -- HL121197/HL/NHLBI NIH HHS/ -- HL71140/HL/NHLBI NIH HHS/ -- HL78931/HL/NHLBI NIH HHS/ -- R01 HL111770/HL/NHLBI NIH HHS/ -- R01 HL116997/HL/NHLBI NIH HHS/ -- R01 HL121197/HL/NHLBI NIH HHS/ -- England -- Nature. 2014 Oct 2;514(7520):102-6. doi: 10.1038/nature13596. Epub 2014 Aug 10.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA [2] Division of Cardiovascular Medicine, Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, USA. ; 1] Division of Cardiovascular Medicine, Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, USA [2]. ; Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA. ; Division of Cardiovascular Medicine, Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, USA. ; Stanford Genome Technology Center, Stanford University School of Medicine, Stanford, California 94305, USA. ; Department of Genetics, Pediatrics, and Medicine (Cardiology), Albert Einstein College of Medicine of Yeshiva University, 1301 Morris Park Avenue, Price Center 420, Bronx, New York 10461, USA. ; Department of Pediatrics, Stanford University School of Medicine, Stanford, California 94305, USA. ; Del E. Webb Neuroscience, Aging &Stem Cell Research Center, Sanford/Burnham Medical Research Institute, La Jolla, California 92037, USA. ; 1] Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA [2] Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA [3] Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25119045" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Cardiac Myosins/genetics ; Cardiomegaly/*genetics/*pathology/prevention & control ; Cardiomyopathies/genetics/pathology/prevention & control ; Chromatin/genetics/metabolism ; Chromatin Assembly and Disassembly ; DNA Helicases/antagonists & inhibitors/chemistry/genetics/metabolism ; Feedback, Physiological ; Heart Failure/genetics/pathology/prevention & control ; Histone Deacetylases/metabolism ; Humans ; Mice ; Myocardium/metabolism/pathology ; Myosin Heavy Chains/*genetics ; Nuclear Proteins/antagonists & inhibitors/chemistry/genetics/metabolism ; Organ Specificity ; Poly(ADP-ribose) Polymerases/metabolism ; Protein Binding ; Protein Structure, Tertiary ; RNA, Long Noncoding/antagonists & inhibitors/*genetics/metabolism ; Transcription Factors/antagonists & inhibitors/chemistry/genetics/metabolism
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  • 14
    Publication Date: 2014-07-22
    Description: Clear cell renal cell carcinoma (ccRCC), the most common form of kidney cancer, is characterized by elevated glycogen levels and fat deposition. These consistent metabolic alterations are associated with normoxic stabilization of hypoxia-inducible factors (HIFs) secondary to von Hippel-Lindau (VHL) mutations that occur in over 90% of ccRCC tumours. However, kidney-specific VHL deletion in mice fails to elicit ccRCC-specific metabolic phenotypes and tumour formation, suggesting that additional mechanisms are essential. Recent large-scale sequencing analyses revealed the loss of several chromatin remodelling enzymes in a subset of ccRCC (these included polybromo-1, SET domain containing 2 and BRCA1-associated protein-1, among others), indicating that epigenetic perturbations are probably important contributors to the natural history of this disease. Here we used an integrative approach comprising pan-metabolomic profiling and metabolic gene set analysis and determined that the gluconeogenic enzyme fructose-1,6-bisphosphatase 1 (FBP1) is uniformly depleted in over six hundred ccRCC tumours examined. Notably, the human FBP1 locus resides on chromosome 9q22, the loss of which is associated with poor prognosis for ccRCC patients. Our data further indicate that FBP1 inhibits ccRCC progression through two distinct mechanisms. First, FBP1 antagonizes glycolytic flux in renal tubular epithelial cells, the presumptive ccRCC cell of origin, thereby inhibiting a potential Warburg effect. Second, in pVHL (the protein encoded by the VHL gene)-deficient ccRCC cells, FBP1 restrains cell proliferation, glycolysis and the pentose phosphate pathway in a catalytic-activity-independent manner, by inhibiting nuclear HIF function via direct interaction with the HIF inhibitory domain. This unique dual function of the FBP1 protein explains its ubiquitous loss in ccRCC, distinguishing FBP1 from previously identified tumour suppressors that are not consistently mutated in all tumours.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4162811/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4162811/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Li, Bo -- Qiu, Bo -- Lee, David S M -- Walton, Zandra E -- Ochocki, Joshua D -- Mathew, Lijoy K -- Mancuso, Anthony -- Gade, Terence P F -- Keith, Brian -- Nissim, Itzhak -- Simon, M Celeste -- CA104838/CA/NCI NIH HHS/ -- DK053761/DK/NIDDK NIH HHS/ -- F30 CA177106/CA/NCI NIH HHS/ -- F32 CA192758/CA/NCI NIH HHS/ -- P01 CA104838/CA/NCI NIH HHS/ -- P30 CA016520/CA/NCI NIH HHS/ -- R01 DK053761/DK/NIDDK NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2014 Sep 11;513(7517):251-5. doi: 10.1038/nature13557. Epub 2014 Jul 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. ; 1] Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Howard Hughes Medical Institute, Philadelphia, Pennsylvania 19104, USA. ; 1] Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Department of Cancer Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. ; 1] Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Department of Cancer Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [3] Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. ; Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. ; 1] Department of Pediatrics, Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Division of Child Development and Metabolic Disease, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA. ; 1] Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Howard Hughes Medical Institute, Philadelphia, Pennsylvania 19104, USA [3] Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25043030" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Basic Helix-Loop-Helix Transcription Factors/metabolism ; Carcinoma, Renal Cell/*enzymology/genetics/physiopathology ; Cell Line ; Cell Line, Tumor ; Cell Proliferation ; Disease Progression ; Epithelial Cells/metabolism ; Fructose-Bisphosphatase/chemistry/genetics/*metabolism ; Glycolysis ; Humans ; Kidney Neoplasms/*enzymology/genetics/physiopathology ; Models, Molecular ; NADP/metabolism ; Protein Structure, Tertiary ; Swine
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  • 15
    Publication Date: 2014-08-15
    Description: Neurotransmitter-gated ion channels of the Cys-loop receptor family mediate fast neurotransmission throughout the nervous system. The molecular processes of neurotransmitter binding, subsequent opening of the ion channel and ion permeation remain poorly understood. Here we present the X-ray structure of a mammalian Cys-loop receptor, the mouse serotonin 5-HT3 receptor, at 3.5 A resolution. The structure of the proteolysed receptor, made up of two fragments and comprising part of the intracellular domain, was determined in complex with stabilizing nanobodies. The extracellular domain reveals the detailed anatomy of the neurotransmitter binding site capped by a nanobody. The membrane domain delimits an aqueous pore with a 4.6 A constriction. In the intracellular domain, a bundle of five intracellular helices creates a closed vestibule where lateral portals are obstructed by loops. This 5-HT3 receptor structure, revealing part of the intracellular domain, expands the structural basis for understanding the operating mechanism of mammalian Cys-loop receptors.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hassaine, Gherici -- Deluz, Cedric -- Grasso, Luigino -- Wyss, Romain -- Tol, Menno B -- Hovius, Ruud -- Graff, Alexandra -- Stahlberg, Henning -- Tomizaki, Takashi -- Desmyter, Aline -- Moreau, Christophe -- Li, Xiao-Dan -- Poitevin, Frederic -- Vogel, Horst -- Nury, Hugues -- England -- Nature. 2014 Aug 21;512(7514):276-81. doi: 10.1038/nature13552. Epub 2014 Aug 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Laboratory of Physical Chemistry of Polymers and Membranes, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland [2] [3] Theranyx, 163 Avenue de Luminy, 13288 Marseille, France. ; 1] Laboratory of Physical Chemistry of Polymers and Membranes, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland [2]. ; Laboratory of Physical Chemistry of Polymers and Membranes, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland. ; Center for Cellular Imaging and NanoAnalytics, Biozentrum, University of Basel, CH-4058 Basel, Switzerland. ; Swiss Light Source, Paul Scherrer Institute, CH-5234 Villigen, Switzerland. ; Architecture et Fonction des Macromolecules Biologiques, CNRS UMR 7257 and Universite Aix-Marseille, F-13288 Marseille, France. ; 1] Universite Grenoble Alpes, IBS, F-38000 Grenoble, France [2] CNRS, IBS, F-38000 Grenoble, France [3] CEA, DSV, IBS, F-38000 Grenoble, France. ; Laboratory of Biomolecular Research, Paul Scherrer Institute, CH-5232 Villigen, Switzerland. ; Unite de Dynamique Structurale des Macromolecules, Institut Pasteur, CNRS UMR3528, F-75015 Paris, France. ; 1] Laboratory of Physical Chemistry of Polymers and Membranes, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland [2] Universite Grenoble Alpes, IBS, F-38000 Grenoble, France [3] CNRS, IBS, F-38000 Grenoble, France [4] CEA, DSV, IBS, F-38000 Grenoble, France.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25119048" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Binding Sites ; Crystallography, X-Ray ; Mice ; Models, Molecular ; Molecular Sequence Data ; Neurotransmitter Agents/metabolism ; Protein Structure, Quaternary ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; Receptors, Serotonin, 5-HT3/*chemistry/metabolism
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  • 16
    Publication Date: 2014-07-22
    Description: The gamma-secretase complex, comprising presenilin 1 (PS1), PEN-2, APH-1 and nicastrin, is a membrane-embedded protease that controls a number of important cellular functions through substrate cleavage. Aberrant cleavage of the amyloid precursor protein (APP) results in aggregation of amyloid-beta, which accumulates in the brain and consequently causes Alzheimer's disease. Here we report the three-dimensional structure of an intact human gamma-secretase complex at 4.5 A resolution, determined by cryo-electron-microscopy single-particle analysis. The gamma-secretase complex comprises a horseshoe-shaped transmembrane domain, which contains 19 transmembrane segments (TMs), and a large extracellular domain (ECD) from nicastrin, which sits immediately above the hollow space formed by the TM horseshoe. Intriguingly, nicastrin ECD is structurally similar to a large family of peptidases exemplified by the glutamate carboxypeptidase PSMA. This structure serves as an important basis for understanding the functional mechanisms of the gamma-secretase complex.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4134323/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4134323/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lu, Peilong -- Bai, Xiao-chen -- Ma, Dan -- Xie, Tian -- Yan, Chuangye -- Sun, Linfeng -- Yang, Guanghui -- Zhao, Yanyu -- Zhou, Rui -- Scheres, Sjors H W -- Shi, Yigong -- MC_UP_A025_1013/Medical Research Council/United Kingdom -- England -- Nature. 2014 Aug 14;512(7513):166-70. doi: 10.1038/nature13567. Epub 2014 Jun 29.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [2] Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [3]. ; 1] MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK [2]. ; 1] Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [2] Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China. ; 1] Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [2] State Key Laboratory of Bio-membrane and Membrane Biotechnology, Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China. ; MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25043039" target="_blank"〉PubMed〈/a〉
    Keywords: Amyloid Precursor Protein Secretases/*chemistry ; Cryoelectron Microscopy ; Crystallography, X-Ray ; Humans ; *Models, Molecular ; Protein Structure, Tertiary
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  • 17
    Publication Date: 2014-05-13
    Description: Sulphur is an essential element for life and is ubiquitous in living systems. Yet how the sulphur atom is incorporated into many sulphur-containing secondary metabolites is poorly understood. For bond formation between carbon and sulphur in primary metabolites, the major ionic sulphur sources are the persulphide and thiocarboxylate groups on sulphur-carrier (donor) proteins. Each group is post-translationally generated through the action of a specific activating enzyme. In all reported bacterial cases, the gene encoding the enzyme that catalyses the carbon-sulphur bond formation reaction and that encoding the cognate sulphur-carrier protein exist in the same gene cluster. To study the production of the 2-thiosugar moiety in BE-7585A, an antibiotic from Amycolatopsis orientalis, we identified a putative 2-thioglucose synthase, BexX, whose protein sequence and mode of action seem similar to those of ThiG, the enzyme that catalyses thiazole formation in thiamine biosynthesis. However, no gene encoding a sulphur-carrier protein could be located in the BE-7585A cluster. Subsequent genome sequencing uncovered a few genes encoding sulphur-carrier proteins that are probably involved in the biosynthesis of primary metabolites but only one activating enzyme gene in the A. orientalis genome. Further experiments showed that this activating enzyme can adenylate each of these sulphur-carrier proteins and probably also catalyses the subsequent thiolation, through its rhodanese domain. A proper combination of these sulphur-delivery systems is effective for BexX-catalysed 2-thioglucose production. The ability of BexX to selectively distinguish sulphur-carrier proteins is given a structural basis using X-ray crystallography. This study is, to our knowledge, the first complete characterization of thiosugar formation in nature and also demonstrates the receptor promiscuity of the A. orientalis sulphur-delivery system. Our results also show that co-opting the sulphur-delivery machinery of primary metabolism for the biosynthesis of sulphur-containing natural products is probably a general strategy found in nature.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4082789/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4082789/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sasaki, Eita -- Zhang, Xuan -- Sun, He G -- Lu, Mei-yeh Jade -- Liu, Tsung-lin -- Ou, Albert -- Li, Jeng-yi -- Chen, Yu-hsiang -- Ealick, Steven E -- Liu, Hung-wen -- DK67081/DK/NIDDK NIH HHS/ -- GM035906/GM/NIGMS NIH HHS/ -- GM103403/GM/NIGMS NIH HHS/ -- GM103485/GM/NIGMS NIH HHS/ -- P41 GM103403/GM/NIGMS NIH HHS/ -- P41 GM103485/GM/NIGMS NIH HHS/ -- R01 DK067081/DK/NIDDK NIH HHS/ -- R01 GM035906/GM/NIGMS NIH HHS/ -- England -- Nature. 2014 Jun 19;510(7505):427-31. doi: 10.1038/nature13256. Epub 2014 May 11.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, USA. ; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA. ; Division of Medicinal Chemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712, USA. ; 1] Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan [2] Genomics Research Center, Academia Sinica, Taipei 115, Taiwan. ; 1] Genomics Research Center, Academia Sinica, Taipei 115, Taiwan [2] Institute of Bioinformatics and Biosignal Transduction, National Cheng-Kung University, Tainan 701, Taiwan. ; Genomics Research Center, Academia Sinica, Taipei 115, Taiwan. ; Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan. ; 1] Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, USA [2] Division of Medicinal Chemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24814342" target="_blank"〉PubMed〈/a〉
    Keywords: Actinomycetales/*enzymology/*genetics/metabolism ; Carrier Proteins/chemistry/*metabolism ; Catalytic Domain ; Genome, Bacterial/genetics ; Ligases/*chemistry/genetics/metabolism ; Models, Molecular ; Molecular Sequence Data ; Protein Structure, Tertiary ; Sulfur/*metabolism ; Thiosugars/*metabolism
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  • 18
    Publication Date: 2014-07-22
    Description: Mutations that deregulate Notch1 and Ras/phosphoinositide 3 kinase (PI3K)/Akt signalling are prevalent in T-cell acute lymphoblastic leukaemia (T-ALL), and often coexist. Here we show that the PI3K inhibitor GDC-0941 is active against primary T-ALLs from wild-type and Kras(G12D) mice, and addition of the MEK inhibitor PD0325901 increases its efficacy. Mice invariably relapsed after treatment with drug-resistant clones, most of which unexpectedly had reduced levels of activated Notch1 protein, downregulated many Notch1 target genes, and exhibited cross-resistance to gamma-secretase inhibitors. Multiple resistant primary T-ALLs that emerged in vivo did not contain somatic Notch1 mutations present in the parental leukaemia. Importantly, resistant clones upregulated PI3K signalling. Consistent with these data, inhibiting Notch1 activated the PI3K pathway, providing a likely mechanism for selection against oncogenic Notch1 signalling. These studies validate PI3K as a therapeutic target in T-ALL and raise the unexpected possibility that dual inhibition of PI3K and Notch1 signalling could promote drug resistance in T-ALL.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4213126/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4213126/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dail, Monique -- Wong, Jason -- Lawrence, Jessica -- O'Connor, Daniel -- Nakitandwe, Joy -- Chen, Shann-Ching -- Xu, Jin -- Lee, Leslie B -- Akagi, Keiko -- Li, Qing -- Aster, Jon C -- Pear, Warren S -- Downing, James R -- Sampath, Deepak -- Shannon, Kevin -- K08 CA134649/CA/NCI NIH HHS/ -- K99 CA157950/CA/NCI NIH HHS/ -- P01 CA119070/CA/NCI NIH HHS/ -- P30 CA021765/CA/NCI NIH HHS/ -- R01 CA180037/CA/NCI NIH HHS/ -- R37 CA072614/CA/NCI NIH HHS/ -- R37 CA72614/CA/NCI NIH HHS/ -- U01 CA084221/CA/NCI NIH HHS/ -- England -- Nature. 2014 Sep 25;513(7519):512-6. doi: 10.1038/nature13495. Epub 2014 Jul 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pediatrics and Benniof Children's Hospital, University of California, San Francisco, California 94143, USA. ; Department of Pathology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA. ; Department of Translational Oncology, Genentech Inc., South San Francisco, California 94080, USA. ; Department of Molecular Virology, Immunology and Medical Genetics, Ohio State University, Columbus, Ohio 43210, USA. ; Division of Haematology/Oncology, Department of Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA. ; Department of Pathology, Brigham &Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA. ; Abramson Family Cancer Research Institute and the Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25043004" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Benzamides/pharmacology/therapeutic use ; Clone Cells/drug effects/metabolism/pathology ; Diphenylamine/analogs & derivatives/pharmacology/therapeutic use ; Down-Regulation/drug effects ; *Drug Resistance, Neoplasm/drug effects/genetics ; Drug Synergism ; Genes, ras/genetics ; Indazoles/*pharmacology/therapeutic use ; Male ; Mice ; Mice, Inbred C57BL ; Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors ; Phosphatidylinositol 3-Kinases/*antagonists & inhibitors ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/*drug ; therapy/*genetics/metabolism/pathology ; Protein Kinase Inhibitors/*pharmacology/therapeutic use ; Protein Structure, Tertiary ; Proto-Oncogene Proteins c-akt/metabolism ; Receptor, Notch1/chemistry/deficiency/genetics/*metabolism ; Signal Transduction/drug effects ; Sulfonamides/*pharmacology/therapeutic use
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  • 19
    Publication Date: 2014-03-05
    Description: Recognition of modified histones by 'reader' proteins plays a critical role in the regulation of chromatin. H3K36 trimethylation (H3K36me3) is deposited onto the nucleosomes in the transcribed regions after RNA polymerase II elongation. In yeast, this mark in turn recruits epigenetic regulators to reset the chromatin to a relatively repressive state, thus suppressing cryptic transcription. However, much less is known about the role of H3K36me3 in transcription regulation in mammals. This is further complicated by the transcription-coupled incorporation of the histone variant H3.3 in gene bodies. Here we show that the candidate tumour suppressor ZMYND11 specifically recognizes H3K36me3 on H3.3 (H3.3K36me3) and regulates RNA polymerase II elongation. Structural studies show that in addition to the trimethyl-lysine binding by an aromatic cage within the PWWP domain, the H3.3-dependent recognition is mediated by the encapsulation of the H3.3-specific 'Ser 31' residue in a composite pocket formed by the tandem bromo-PWWP domains of ZMYND11. Chromatin immunoprecipitation followed by sequencing shows a genome-wide co-localization of ZMYND11 with H3K36me3 and H3.3 in gene bodies, and its occupancy requires the pre-deposition of H3.3K36me3. Although ZMYND11 is associated with highly expressed genes, it functions as an unconventional transcription co-repressor by modulating RNA polymerase II at the elongation stage. ZMYND11 is critical for the repression of a transcriptional program that is essential for tumour cell growth; low expression levels of ZMYND11 in breast cancer patients correlate with worse prognosis. Consistently, overexpression of ZMYND11 suppresses cancer cell growth in vitro and tumour formation in mice. Together, this study identifies ZMYND11 as an H3.3-specific reader of H3K36me3 that links the histone-variant-mediated transcription elongation control to tumour suppression.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4142212/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4142212/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wen, Hong -- Li, Yuanyuan -- Xi, Yuanxin -- Jiang, Shiming -- Stratton, Sabrina -- Peng, Danni -- Tanaka, Kaori -- Ren, Yongfeng -- Xia, Zheng -- Wu, Jun -- Li, Bing -- Barton, Michelle C -- Li, Wei -- Li, Haitao -- Shi, Xiaobing -- CA016672/CA/NCI NIH HHS/ -- P30 CA016672/CA/NCI NIH HHS/ -- R01 GM090077/GM/NIGMS NIH HHS/ -- R01 HG007538/HG/NHGRI NIH HHS/ -- R01GM090077/GM/NIGMS NIH HHS/ -- R01HG007538/HG/NHGRI NIH HHS/ -- England -- Nature. 2014 Apr 10;508(7495):263-8. doi: 10.1038/nature13045. Epub 2014 Mar 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Biochemistry and Molecular Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA [2] Center for Cancer Epigenetics, Center for Genetics and Genomics, and Center for Stem Cell and Developmental Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA [3]. ; 1] MOE Key Laboratory of Protein Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China [2] Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China [3]. ; 1] Dan L. Duncan Cancer Center, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA [2]. ; Department of Biochemistry and Molecular Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA. ; 1] MOE Key Laboratory of Protein Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China [2] Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China. ; Dan L. Duncan Cancer Center, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA. ; Department of Molecular Biology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA. ; 1] Department of Biochemistry and Molecular Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA [2] Center for Cancer Epigenetics, Center for Genetics and Genomics, and Center for Stem Cell and Developmental Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA [3] Genes and Development Graduate Program, The University of Texas Graduate School of Biomedical Sciences, Houston, Teaxs 77030, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24590075" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Breast Neoplasms/*genetics/metabolism/*pathology ; Carrier Proteins/chemistry/*metabolism ; Chromatin/genetics/metabolism ; Co-Repressor Proteins/chemistry/metabolism ; Crystallography, X-Ray ; Disease-Free Survival ; Female ; Gene Expression Regulation, Neoplastic/genetics ; Histones/chemistry/*metabolism ; Humans ; Lysine/*metabolism ; Methylation ; Mice ; Mice, Nude ; Models, Molecular ; Molecular Sequence Data ; Oncogenes/genetics ; Prognosis ; Protein Binding ; Protein Conformation ; Protein Structure, Tertiary ; RNA Polymerase II/*metabolism ; Substrate Specificity ; *Transcription Elongation, Genetic
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  • 20
    Publication Date: 2014-06-27
    Description: The polyketide synthase (PKS) mega-enzyme assembly line uses a modular architecture to synthesize diverse and bioactive natural products that often constitute the core structures or complete chemical entities for many clinically approved therapeutic agents. The architecture of a full-length PKS module from the pikromycin pathway of Streptomyces venezuelae creates a reaction chamber for the intramodule acyl carrier protein (ACP) domain that carries building blocks and intermediates between acyltransferase, ketosynthase and ketoreductase active sites (see accompanying paper). Here we determine electron cryo-microscopy structures of a full-length pikromycin PKS module in three key biochemical states of its catalytic cycle. Each biochemical state was confirmed by bottom-up liquid chromatography/Fourier transform ion cyclotron resonance mass spectrometry. The ACP domain is differentially and precisely positioned after polyketide chain substrate loading on the active site of the ketosynthase, after extension to the beta-keto intermediate, and after beta-hydroxy product generation. The structures reveal the ACP dynamics for sequential interactions with catalytic domains within the reaction chamber, and for transferring the elongated and processed polyketide substrate to the next module in the PKS pathway. During the enzymatic cycle the ketoreductase domain undergoes dramatic conformational rearrangements that enable optimal positioning for reductive processing of the ACP-bound polyketide chain elongation intermediate. These findings have crucial implications for the design of functional PKS modules, and for the engineering of pathways to generate pharmacologically relevant molecules.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4074775/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4074775/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Whicher, Jonathan R -- Dutta, Somnath -- Hansen, Douglas A -- Hale, Wendi A -- Chemler, Joseph A -- Dosey, Annie M -- Narayan, Alison R H -- Hakansson, Kristina -- Sherman, David H -- Smith, Janet L -- Skiniotis, Georgios -- 1R21CA138331-01A1/CA/NCI NIH HHS/ -- DK042303/DK/NIDDK NIH HHS/ -- DK090165/DK/NIDDK NIH HHS/ -- GM076477/GM/NIGMS NIH HHS/ -- R01 DK042303/DK/NIDDK NIH HHS/ -- R01 DK090165/DK/NIDDK NIH HHS/ -- R01 GM076477/GM/NIGMS NIH HHS/ -- T32 GM008597/GM/NIGMS NIH HHS/ -- England -- Nature. 2014 Jun 26;510(7506):560-4. doi: 10.1038/nature13409. Epub 2014 Jun 18.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA [2] Chemical Biology Graduate Program, University of Michigan, Ann Arbor, Michigan 48109, USA [3]. ; 1] Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA [2]. ; 1] Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA [2] Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA. ; Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA. ; Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA. ; 1] Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA [2] Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA [3] Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA [4] Department of Microbiology & Immunology, University of Michigan, Ann Arbor, Michigan 48109, USA. ; 1] Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA [2] Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24965656" target="_blank"〉PubMed〈/a〉
    Keywords: Acyl Carrier Protein/chemistry/metabolism/ultrastructure ; Acyltransferases/chemistry/metabolism/ultrastructure ; Alcohol Oxidoreductases/chemistry/metabolism/ultrastructure ; Bacterial Proteins/chemistry/metabolism/ultrastructure ; *Biocatalysis ; Catalytic Domain ; Cryoelectron Microscopy ; Macrolides/metabolism ; Models, Molecular ; Polyketide Synthases/*chemistry/*metabolism/ultrastructure ; Protein Structure, Tertiary ; Streptomyces/*enzymology
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  • 21
    Publication Date: 2014-07-22
    Description: Metabotropic glutamate receptors are class C G-protein-coupled receptors which respond to the neurotransmitter glutamate. Structural studies have been restricted to the amino-terminal extracellular domain, providing little understanding of the membrane-spanning signal transduction domain. Metabotropic glutamate receptor 5 is of considerable interest as a drug target in the treatment of fragile X syndrome, autism, depression, anxiety, addiction and movement disorders. Here we report the crystal structure of the transmembrane domain of the human receptor in complex with the negative allosteric modulator, mavoglurant. The structure provides detailed insight into the architecture of the transmembrane domain of class C receptors including the precise location of the allosteric binding site within the transmembrane domain and key micro-switches which regulate receptor signalling. This structure also provides a model for all class C G-protein-coupled receptors and may aid in the design of new small-molecule drugs for the treatment of brain disorders.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dore, Andrew S -- Okrasa, Krzysztof -- Patel, Jayesh C -- Serrano-Vega, Maria -- Bennett, Kirstie -- Cooke, Robert M -- Errey, James C -- Jazayeri, Ali -- Khan, Samir -- Tehan, Ben -- Weir, Malcolm -- Wiggin, Giselle R -- Marshall, Fiona H -- England -- Nature. 2014 Jul 31;511(7511):557-62. doi: 10.1038/nature13396. Epub 2014 Jul 6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Heptares Therapeutics Ltd, BioPark, Broadwater Road, Welwyn Garden City, Hertfordshire AL7 3AX, UK [2]. ; Heptares Therapeutics Ltd, BioPark, Broadwater Road, Welwyn Garden City, Hertfordshire AL7 3AX, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25042998" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Binding Sites ; Crystallography, X-Ray ; HEK293 Cells ; Humans ; *Models, Molecular ; Protein Structure, Tertiary ; Receptor, Metabotropic Glutamate 5/*chemistry ; Rhodopsin/chemistry
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  • 22
    Publication Date: 2014-04-22
    Description: The capacity of numerous bacterial species to tolerate antibiotics and other toxic compounds arises in part from the activity of energy-dependent transporters. In Gram-negative bacteria, many of these transporters form multicomponent 'pumps' that span both inner and outer membranes and are driven energetically by a primary or secondary transporter component. A model system for such a pump is the acridine resistance complex of Escherichia coli. This pump assembly comprises the outer-membrane channel TolC, the secondary transporter AcrB located in the inner membrane, and the periplasmic AcrA, which bridges these two integral membrane proteins. The AcrAB-TolC efflux pump is able to transport vectorially a diverse array of compounds with little chemical similarity, thus conferring resistance to a broad spectrum of antibiotics. Homologous complexes are found in many Gram-negative species, including in animal and plant pathogens. Crystal structures are available for the individual components of the pump and have provided insights into substrate recognition, energy coupling and the transduction of conformational changes associated with the transport process. However, how the subunits are organized in the pump, their stoichiometry and the details of their interactions are not known. Here we present the pseudo-atomic structure of a complete multidrug efflux pump in complex with a modulatory protein partner from E. coli. The model defines the quaternary organization of the pump, identifies key domain interactions, and suggests a cooperative process for channel assembly and opening. These findings illuminate the basis for drug resistance in numerous pathogenic bacterial species.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4361902/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4361902/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Du, Dijun -- Wang, Zhao -- James, Nathan R -- Voss, Jarrod E -- Klimont, Ewa -- Ohene-Agyei, Thelma -- Venter, Henrietta -- Chiu, Wah -- Luisi, Ben F -- 076846/Wellcome Trust/United Kingdom -- 094229/Wellcome Trust/United Kingdom -- P41 GM103832/GM/NIGMS NIH HHS/ -- P41GM103832/GM/NIGMS NIH HHS/ -- Wellcome Trust/United Kingdom -- England -- Nature. 2014 May 22;509(7501):512-5. doi: 10.1038/nature13205. Epub 2014 Apr 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1GA, UK. ; National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA. ; Department of Pharmacology, Tennis Court Road, Cambridge CB2 1PD, UK. ; School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, South Australia 5000, Australia.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24747401" target="_blank"〉PubMed〈/a〉
    Keywords: Bacterial Outer Membrane Proteins/*chemistry/metabolism ; Carrier Proteins/*chemistry/*metabolism ; Cryoelectron Microscopy ; Crystallography, X-Ray ; Drug Resistance, Bacterial ; Escherichia coli/*chemistry ; Escherichia coli Proteins/*chemistry/*metabolism ; Lipoproteins/*chemistry/metabolism ; Membrane Transport Proteins/*chemistry/metabolism ; Models, Molecular ; Multidrug Resistance-Associated Proteins/*chemistry/*metabolism ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism
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  • 23
    Publication Date: 2014-01-10
    Description: The human immunodeficiency virus (HIV)-1 protein Vif has a central role in the neutralization of host innate defences by hijacking cellular proteasomal degradation pathways to subvert the antiviral activity of host restriction factors; however, the underlying mechanism by which Vif achieves this remains unclear. Here we report a crystal structure of the Vif-CBF-beta-CUL5-ELOB-ELOC complex. The structure reveals that Vif, by means of two domains, organizes formation of the pentameric complex by interacting with CBF-beta, CUL5 and ELOC. The larger domain (alpha/beta domain) of Vif binds to the same side of CBF-beta as RUNX1, indicating that Vif and RUNX1 are exclusive for CBF-beta binding. Interactions of the smaller domain (alpha-domain) of Vif with ELOC and CUL5 are cooperative and mimic those of SOCS2 with the latter two proteins. A unique zinc-finger motif of Vif, which is located between the two Vif domains, makes no contacts with the other proteins but stabilizes the conformation of the alpha-domain, which may be important for Vif-CUL5 interaction. Together, our data reveal the structural basis for Vif hijacking of the CBF-beta and CUL5 E3 ligase complex, laying a foundation for rational design of novel anti-HIV drugs.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Guo, Yingying -- Dong, Liyong -- Qiu, Xiaolin -- Wang, Yishu -- Zhang, Bailing -- Liu, Hongnan -- Yu, You -- Zang, Yi -- Yang, Maojun -- Huang, Zhiwei -- England -- Nature. 2014 Jan 9;505(7482):229-33. doi: 10.1038/nature12884.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] School of Life Science and Technology, Harbin Institute of Technology, Harbin 150080, China [2]. ; School of Life Science and Technology, Harbin Institute of Technology, Harbin 150080, China. ; MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24402281" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Core Binding Factor Alpha 2 Subunit/metabolism ; Core Binding Factor beta Subunit/*chemistry/*metabolism ; Crystallography, X-Ray ; Cullin Proteins/*chemistry/*metabolism ; Humans ; Models, Molecular ; Molecular Sequence Data ; Multiprotein Complexes/chemistry/metabolism ; Protein Binding ; Protein Stability ; Protein Structure, Tertiary ; Suppressor of Cytokine Signaling Proteins ; Transcription Factors/chemistry/metabolism ; vif Gene Products, Human Immunodeficiency Virus/*chemistry/*metabolism
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  • 24
    Publication Date: 2014-06-10
    Description: Type-A gamma-aminobutyric acid receptors (GABAARs) are the principal mediators of rapid inhibitory synaptic transmission in the human brain. A decline in GABAAR signalling triggers hyperactive neurological disorders such as insomnia, anxiety and epilepsy. Here we present the first three-dimensional structure of a GABAAR, the human beta3 homopentamer, at 3 A resolution. This structure reveals architectural elements unique to eukaryotic Cys-loop receptors, explains the mechanistic consequences of multiple human disease mutations and shows an unexpected structural role for a conserved N-linked glycan. The receptor was crystallized bound to a previously unknown agonist, benzamidine, opening a new avenue for the rational design of GABAAR modulators. The channel region forms a closed gate at the base of the pore, representative of a desensitized state. These results offer new insights into the signalling mechanisms of pentameric ligand-gated ion channels and enhance current understanding of GABAergic neurotransmission.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4167603/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4167603/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Miller, Paul S -- Aricescu, A Radu -- 084655/Wellcome Trust/United Kingdom -- 090532/Wellcome Trust/United Kingdom -- 090532/Z/09/Z/Wellcome Trust/United Kingdom -- G0700232/Medical Research Council/United Kingdom -- MR/L009609/1/Medical Research Council/United Kingdom -- England -- Nature. 2014 Aug 21;512(7514):270-5. doi: 10.1038/nature13293. Epub 2014 Jun 8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24909990" target="_blank"〉PubMed〈/a〉
    Keywords: Benzamidines/chemistry/metabolism/pharmacology ; Binding Sites ; Cell Membrane/chemistry/metabolism ; Conserved Sequence ; Crystallography, X-Ray ; Drug Design ; GABA-A Receptor Agonists/chemistry/metabolism/pharmacology ; Genetic Predisposition to Disease ; Glycosylation ; Humans ; Models, Molecular ; Mutation/genetics ; Polysaccharides/chemistry/metabolism ; Protein Structure, Quaternary ; Protein Structure, Tertiary ; Protein Subunits ; Receptors, GABA-A/*chemistry/genetics ; Synaptic Transmission
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  • 25
    Publication Date: 2014-07-22
    Description: Photosynthesis, a process catalysed by plants, algae and cyanobacteria converts sunlight to energy thus sustaining all higher life on Earth. Two large membrane protein complexes, photosystem I and II (PSI and PSII), act in series to catalyse the light-driven reactions in photosynthesis. PSII catalyses the light-driven water splitting process, which maintains the Earth's oxygenic atmosphere. In this process, the oxygen-evolving complex (OEC) of PSII cycles through five states, S0 to S4, in which four electrons are sequentially extracted from the OEC in four light-driven charge-separation events. Here we describe time resolved experiments on PSII nano/microcrystals from Thermosynechococcus elongatus performed with the recently developed technique of serial femtosecond crystallography. Structures have been determined from PSII in the dark S1 state and after double laser excitation (putative S3 state) at 5 and 5.5 A resolution, respectively. The results provide evidence that PSII undergoes significant conformational changes at the electron acceptor side and at the Mn4CaO5 core of the OEC. These include an elongation of the metal cluster, accompanied by changes in the protein environment, which could allow for binding of the second substrate water molecule between the more distant protruding Mn (referred to as the 'dangler' Mn) and the Mn3CaOx cubane in the S2 to S3 transition, as predicted by spectroscopic and computational studies. This work shows the great potential for time-resolved serial femtosecond crystallography for investigation of catalytic processes in biomolecules.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kupitz, Christopher -- Basu, Shibom -- Grotjohann, Ingo -- Fromme, Raimund -- Zatsepin, Nadia A -- Rendek, Kimberly N -- Hunter, Mark S -- Shoeman, Robert L -- White, Thomas A -- Wang, Dingjie -- James, Daniel -- Yang, Jay-How -- Cobb, Danielle E -- Reeder, Brenda -- Sierra, Raymond G -- Liu, Haiguang -- Barty, Anton -- Aquila, Andrew L -- Deponte, Daniel -- Kirian, Richard A -- Bari, Sadia -- Bergkamp, Jesse J -- Beyerlein, Kenneth R -- Bogan, Michael J -- Caleman, Carl -- Chao, Tzu-Chiao -- Conrad, Chelsie E -- Davis, Katherine M -- Fleckenstein, Holger -- Galli, Lorenzo -- Hau-Riege, Stefan P -- Kassemeyer, Stephan -- Laksmono, Hartawan -- Liang, Mengning -- Lomb, Lukas -- Marchesini, Stefano -- Martin, Andrew V -- Messerschmidt, Marc -- Milathianaki, Despina -- Nass, Karol -- Ros, Alexandra -- Roy-Chowdhury, Shatabdi -- Schmidt, Kevin -- Seibert, Marvin -- Steinbrener, Jan -- Stellato, Francesco -- Yan, Lifen -- Yoon, Chunhong -- Moore, Thomas A -- Moore, Ana L -- Pushkar, Yulia -- Williams, Garth J -- Boutet, Sebastien -- Doak, R Bruce -- Weierstall, Uwe -- Frank, Matthias -- Chapman, Henry N -- Spence, John C H -- Fromme, Petra -- 1R01GM095583/GM/NIGMS NIH HHS/ -- R01 GM095583/GM/NIGMS NIH HHS/ -- England -- Nature. 2014 Sep 11;513(7517):261-5. doi: 10.1038/nature13453. Epub 2014 Jul 9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA [2]. ; Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA. ; Department of Physics, Arizona State University, Tempe, Arizona 85287, USA. ; 1] Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA [2] Lawrence Livermore National Laboratory, Livermore, California 94550, USA. ; Max-Planck-Institut fur medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany. ; Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany. ; Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA. ; 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] European XFEL GmbH, Notkestrasse 85, 22607 Hamburg, Germany. ; 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] Linac Coherent Light Source, Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA. ; 1] Department of Physics, Arizona State University, Tempe, Arizona 85287, USA [2] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany. ; 1] Max Planck Advanced Study Group, Center for Free-Electron Laser Science (CFEL), Notkestrasse 85, 22607 Hamburg, Germany [2] Max-Planck-Institut fur Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany. ; 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] Department of Physics and Astronomy, Uppsala University, Regementsvagen 1, SE-752 37 Uppsala, Sweden. ; 1] Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA [2] University of Regina, 3737 Wascana Pkwy Regina, Saskatchewan S4S 0A2, Canada. ; Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, Indiana 47907, USA. ; 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany. ; Lawrence Livermore National Laboratory, Livermore, California 94550, USA. ; 1] Max-Planck-Institut fur medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany [2] Max Planck Advanced Study Group, Center for Free-Electron Laser Science (CFEL), Notkestrasse 85, 22607 Hamburg, Germany. ; Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. ; 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] Department ARC Centre of Excellence for Coherent X-ray Science, Department of Physics, University of Melbourne, Parkville VIC 3010, Australia. ; Linac Coherent Light Source, Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA. ; 1] Max-Planck-Institut fur medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany [2] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [3] University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany. ; 1] Linac Coherent Light Source, Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA [2] Uppsala University, Sankt Olofsgatan 10B, 753 12 Uppsala, Sweden. ; 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany [3] Center for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25043005" target="_blank"〉PubMed〈/a〉
    Keywords: *Crystallography, X-Ray ; Cyanobacteria/*chemistry ; *Models, Molecular ; Photosystem II Protein Complex/*chemistry ; Protein Structure, Tertiary
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  • 26
    Publication Date: 2014-07-22
    Description: Ubiquitination is a crucial cellular signalling process, and is controlled on multiple levels. Cullin-RING E3 ubiquitin ligases (CRLs) are regulated by the eight-subunit COP9 signalosome (CSN). CSN inactivates CRLs by removing their covalently attached activator, NEDD8. NEDD8 cleavage by CSN is catalysed by CSN5, a Zn(2+)-dependent isopeptidase that is inactive in isolation. Here we present the crystal structure of the entire approximately 350-kDa human CSN holoenzyme at 3.8 A resolution, detailing the molecular architecture of the complex. CSN has two organizational centres: a horseshoe-shaped ring created by its six proteasome lid-CSN-initiation factor 3 (PCI) domain proteins, and a large bundle formed by the carboxy-terminal alpha-helices of every subunit. CSN5 and its dimerization partner, CSN6, are intricately embedded at the core of the helical bundle. In the substrate-free holoenzyme, CSN5 is autoinhibited, which precludes access to the active site. We find that neddylated CRL binding to CSN is sensed by CSN4, and communicated to CSN5 with the assistance of CSN6, resulting in activation of the deneddylase.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lingaraju, Gondichatnahalli M -- Bunker, Richard D -- Cavadini, Simone -- Hess, Daniel -- Hassiepen, Ulrich -- Renatus, Martin -- Fischer, Eric S -- Thoma, Nicolas H -- England -- Nature. 2014 Aug 14;512(7513):161-5. doi: 10.1038/nature13566. Epub 2014 Jul 16.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland [2] University of Basel, Petersplatz 10, 4003 Basel, Switzerland [3]. ; 1] Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland [2] University of Basel, Petersplatz 10, 4003 Basel, Switzerland. ; Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland. ; Novartis Pharma AG, Institutes for Biomedical Research, Novartis Campus, 4056 Basel, Switzerland.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25043011" target="_blank"〉PubMed〈/a〉
    Keywords: Adaptor Proteins, Signal Transducing ; Catalytic Domain ; Crystallography, X-Ray ; Enzyme Activation ; Humans ; Intracellular Signaling Peptides and Proteins/metabolism ; *Models, Molecular ; Multiprotein Complexes/*chemistry ; Peptide Hydrolases/*chemistry/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Transcription Factors/metabolism
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  • 27
    Publication Date: 2014-05-13
    Description: 2-Oxoglutarate (2OG)-dependent oxygenases have important roles in the regulation of gene expression via demethylation of N-methylated chromatin components and in the hydroxylation of transcription factors and splicing factor proteins. Recently, 2OG-dependent oxygenases that catalyse hydroxylation of transfer RNA and ribosomal proteins have been shown to be important in translation relating to cellular growth, TH17-cell differentiation and translational accuracy. The finding that ribosomal oxygenases (ROXs) occur in organisms ranging from prokaryotes to humans raises questions as to their structural and evolutionary relationships. In Escherichia coli, YcfD catalyses arginine hydroxylation in the ribosomal protein L16; in humans, MYC-induced nuclear antigen (MINA53; also known as MINA) and nucleolar protein 66 (NO66) catalyse histidine hydroxylation in the ribosomal proteins RPL27A and RPL8, respectively. The functional assignments of ROXs open therapeutic possibilities via either ROX inhibition or targeting of differentially modified ribosomes. Despite differences in the residue and protein selectivities of prokaryotic and eukaryotic ROXs, comparison of the crystal structures of E. coli YcfD and Rhodothermus marinus YcfD with those of human MINA53 and NO66 reveals highly conserved folds and novel dimerization modes defining a new structural subfamily of 2OG-dependent oxygenases. ROX structures with and without their substrates support their functional assignments as hydroxylases but not demethylases, and reveal how the subfamily has evolved to catalyse the hydroxylation of different residue side chains of ribosomal proteins. Comparison of ROX crystal structures with those of other JmjC-domain-containing hydroxylases, including the hypoxia-inducible factor asparaginyl hydroxylase FIH and histone N(epsilon)-methyl lysine demethylases, identifies branch points in 2OG-dependent oxygenase evolution and distinguishes between JmjC-containing hydroxylases and demethylases catalysing modifications of translational and transcriptional machinery. The structures reveal that new protein hydroxylation activities can evolve by changing the coordination position from which the iron-bound substrate-oxidizing species reacts. This coordination flexibility has probably contributed to the evolution of the wide range of reactions catalysed by oxygenases.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4066111/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4066111/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Chowdhury, Rasheduzzaman -- Sekirnik, Rok -- Brissett, Nigel C -- Krojer, Tobias -- Ho, Chia-Hua -- Ng, Stanley S -- Clifton, Ian J -- Ge, Wei -- Kershaw, Nadia J -- Fox, Gavin C -- Muniz, Joao R C -- Vollmar, Melanie -- Phillips, Claire -- Pilka, Ewa S -- Kavanagh, Kathryn L -- von Delft, Frank -- Oppermann, Udo -- McDonough, Michael A -- Doherty, Aidan J -- Schofield, Christopher J -- 092809/Wellcome Trust/United Kingdom -- 6947/Cancer Research UK/United Kingdom -- BB/C518230/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- BB/L009846/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- Arthritis Research UK/United Kingdom -- Biotechnology and Biological Sciences Research Council/United Kingdom -- Cancer Research UK/United Kingdom -- Medical Research Council/United Kingdom -- Wellcome Trust/United Kingdom -- England -- Nature. 2014 Jun 19;510(7505):422-6. doi: 10.1038/nature13263. Epub 2014 May 11.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉The Department of Chemistry and Oxford Centre for Integrative Systems Biology, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK. ; 1] The Department of Chemistry and Oxford Centre for Integrative Systems Biology, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK [2]. ; 1] Genome Damage and Stability Centre, University of Sussex, Brighton BN1 9RQ, UK [2]. ; Structural Genomics Consortium, University of Oxford, Headington, Oxford OX3 7DQ, UK. ; Synchrotron SOLEIL, Saint Aubin, 91192 Gif-sur-Yvette Cedex, France. ; 1] Structural Genomics Consortium, University of Oxford, Headington, Oxford OX3 7DQ, UK [2] NIHR Oxford Biomedical Research Unit, Botnar Research Centre, Oxford OX3 7LD, UK. ; Genome Damage and Stability Centre, University of Sussex, Brighton BN1 9RQ, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24814345" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Catalytic Domain ; Conserved Sequence ; Eukaryota/classification/*enzymology ; Humans ; *Models, Molecular ; Oxygenases/*chemistry/metabolism ; Phylogeny ; Prokaryotic Cells/classification/*enzymology ; Protein Folding ; Protein Structure, Tertiary ; Ribosomes/*enzymology ; Sequence Alignment
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  • 28
    Publication Date: 2014-03-05
    Description: Ubiquitin (Ub) has important roles in a wide range of intracellular signalling pathways. In the conventional view, ubiquitin alters the signalling activity of the target protein through covalent modification, but accumulating evidence points to the emerging role of non-covalent interaction between ubiquitin and the target. In the innate immune signalling pathway of a viral RNA sensor, RIG-I, both covalent and non-covalent interactions with K63-linked ubiquitin chains (K63-Ubn) were shown to occur in its signalling domain, a tandem caspase activation and recruitment domain (hereafter referred to as 2CARD). Non-covalent binding of K63-Ubn to 2CARD induces its tetramer formation, a requirement for downstream signal activation. Here we report the crystal structure of the tetramer of human RIG-I 2CARD bound by three chains of K63-Ub2. 2CARD assembles into a helical tetramer resembling a 'lock-washer', in which the tetrameric surface serves as a signalling platform for recruitment and activation of the downstream signalling molecule, MAVS. Ubiquitin chains are bound along the outer rim of the helical trajectory, bridging adjacent subunits of 2CARD and stabilizing the 2CARD tetramer. The combination of structural and functional analyses reveals that binding avidity dictates the K63-linkage and chain-length specificity of 2CARD, and that covalent ubiquitin conjugation of 2CARD further stabilizes the Ub-2CARD interaction and thus the 2CARD tetramer. Our work provides unique insights into the novel types of ubiquitin-mediated signal-activation mechanism, and previously unexpected synergism between the covalent and non-covalent ubiquitin interaction modes.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Peisley, Alys -- Wu, Bin -- Xu, Hui -- Chen, Zhijian J -- Hur, Sun -- R01-GM63692/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2014 May 1;509(7498):110-4. doi: 10.1038/nature13140. Epub 2014 Mar 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115 USA [2] Program in Cellular and Molecular Medicine, Children's Hospital Boston, Boston, Massachusetts 02115, USA. ; Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA. ; 1] Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA [2] Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24590070" target="_blank"〉PubMed〈/a〉
    Keywords: Adaptor Proteins, Signal Transducing/chemistry/metabolism ; Caspases/metabolism ; Crystallography, X-Ray ; DEAD-box RNA Helicases/*chemistry/*metabolism ; Humans ; Models, Molecular ; Protein Binding ; Protein Multimerization ; Protein Stability ; Protein Structure, Quaternary ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; RNA, Viral/analysis/metabolism ; Signal Transduction ; Structure-Activity Relationship ; Substrate Specificity ; Ubiquitin/*chemistry/*metabolism
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  • 29
    Publication Date: 2014-09-12
    Description: Complex I (NADH:ubiquinone oxidoreductase) is essential for oxidative phosphorylation in mammalian mitochondria. It couples electron transfer from NADH to ubiquinone with proton translocation across the energy-transducing inner membrane, providing electrons for respiration and driving ATP synthesis. Mammalian complex I contains 44 different nuclear- and mitochondrial-encoded subunits, with a combined mass of 1 MDa. The 14 conserved 'core' subunits have been structurally defined in the minimal, bacterial complex, but the structures and arrangement of the 30 'supernumerary' subunits are unknown. Here we describe a 5 A resolution structure of complex I from Bos taurus heart mitochondria, a close relative of the human enzyme, determined by single-particle electron cryo-microscopy. We present the structures of the mammalian core subunits that contain eight iron-sulphur clusters and 60 transmembrane helices, identify 18 supernumerary transmembrane helices, and assign and model 14 supernumerary subunits. Thus, we considerably advance knowledge of the structure of mammalian complex I and the architecture of its supernumerary ensemble around the core domains. Our structure provides insights into the roles of the supernumerary subunits in regulation, assembly and homeostasis, and a basis for understanding the effects of mutations that cause a diverse range of human diseases.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4224586/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4224586/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Vinothkumar, Kutti R -- Zhu, Jiapeng -- Hirst, Judy -- MC_U105184322/Medical Research Council/United Kingdom -- MC_U105663141/Medical Research Council/United Kingdom -- U105184322/Medical Research Council/United Kingdom -- U105663141/Medical Research Council/United Kingdom -- England -- Nature. 2014 Nov 6;515(7525):80-4. doi: 10.1038/nature13686. Epub 2014 Sep 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK [2]. ; 1] MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK [2]. ; MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25209663" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Cattle ; Cryoelectron Microscopy ; Electron Transport Complex I/*chemistry/*ultrastructure ; Mitochondria, Heart/enzymology ; Models, Molecular ; Protein Structure, Tertiary ; Protein Subunits/chemistry
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  • 30
    Publication Date: 2014-01-28
    Description: RNA-directed DNA methylation in Arabidopsis thaliana depends on the upstream synthesis of 24-nucleotide small interfering RNAs (siRNAs) by RNA POLYMERASE IV (Pol IV) and downstream synthesis of non-coding transcripts by Pol V. Pol V transcripts are thought to interact with siRNAs which then recruit DOMAINS REARRANGED METHYLTRANSFERASE 2 (DRM2) to methylate DNA. The SU(VAR)3-9 homologues SUVH2 and SUVH9 act in this downstream step but the mechanism of their action is unknown. Here we show that genome-wide Pol V association with chromatin redundantly requires SUVH2 and SUVH9. Although SUVH2 and SUVH9 resemble histone methyltransferases, a crystal structure reveals that SUVH9 lacks a peptide-substrate binding cleft and lacks a properly formed S-adenosyl methionine (SAM)-binding pocket necessary for normal catalysis, consistent with a lack of methyltransferase activity for these proteins. SUVH2 and SUVH9 both contain SRA (SET- and RING-ASSOCIATED) domains capable of binding methylated DNA, suggesting that they function to recruit Pol V through DNA methylation. Consistent with this model, mutation of DNA METHYLTRANSFERASE 1 (MET1) causes loss of DNA methylation, a nearly complete loss of Pol V at its normal locations, and redistribution of Pol V to sites that become hypermethylated. Furthermore, tethering SUVH2 with a zinc finger to an unmethylated site is sufficient to recruit Pol V and establish DNA methylation and gene silencing. These results indicate that Pol V is recruited to DNA methylation through the methyl-DNA binding SUVH2 and SUVH9 proteins, and our mechanistic findings suggest a means for selectively targeting regions of plant genomes for epigenetic silencing.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3963826/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3963826/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Johnson, Lianna M -- Du, Jiamu -- Hale, Christopher J -- Bischof, Sylvain -- Feng, Suhua -- Chodavarapu, Ramakrishna K -- Zhong, Xuehua -- Marson, Giuseppe -- Pellegrini, Matteo -- Segal, David J -- Patel, Dinshaw J -- Jacobsen, Steven E -- F32GM096483-01/GM/NIGMS NIH HHS/ -- GM60398/GM/NIGMS NIH HHS/ -- P30 CA016042/CA/NCI NIH HHS/ -- R37 GM060398/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2014 Mar 6;507(7490):124-8. doi: 10.1038/nature12931. Epub 2014 Jan 22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA [2]. ; 1] Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA [2]. ; Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA. ; 1] Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA [2] Howard Hughes Medical Institute, University of California at Los Angeles, Los Angeles, California 90095, USA. ; 1] Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA [2] Wisconsin Institute for Discovery, Laboratory of Genetics, University of Wisconsin, Madison, Wisconsin 53706, USA. ; Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA. ; Genome Center and Department of Biochemistry and Molecular Medicine, University of California at Davis, Davis, California 95616, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24463519" target="_blank"〉PubMed〈/a〉
    Keywords: *Arabidopsis/enzymology/genetics ; Arabidopsis Proteins/*chemistry/genetics/*metabolism ; Binding Sites/genetics ; Biocatalysis ; Chromatin/chemistry/genetics/metabolism ; Crystallography, X-Ray ; DNA (Cytosine-5-)-Methyltransferase/genetics/metabolism ; *DNA Methylation/genetics ; DNA-Binding Proteins/chemistry/metabolism ; DNA-Directed RNA Polymerases/*metabolism ; Flowers/growth & development ; Gene Expression Regulation, Plant ; Gene Silencing ; Genome, Plant/genetics ; Histone-Lysine N-Methyltransferase/*chemistry/*metabolism ; Models, Molecular ; Mutation/genetics ; Phenotype ; Protein Structure, Tertiary ; Protein Transport ; RNA, Plant/biosynthesis/genetics/metabolism ; RNA, Small Interfering/biosynthesis/genetics/metabolism ; Transcription, Genetic ; Zinc Fingers
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  • 31
    Publication Date: 2014-11-20
    Description: The influenza virus polymerase transcribes or replicates the segmented RNA genome (viral RNA) into viral messenger RNA or full-length copies. To initiate RNA synthesis, the polymerase binds to the conserved 3' and 5' extremities of the viral RNA. Here we present the crystal structure of the heterotrimeric bat influenza A polymerase, comprising subunits PA, PB1 and PB2, bound to its viral RNA promoter. PB1 contains a canonical RNA polymerase fold that is stabilized by large interfaces with PA and PB2. The PA endonuclease and the PB2 cap-binding domain, involved in transcription by cap-snatching, form protrusions facing each other across a solvent channel. The 5' extremity of the promoter folds into a compact hook that is bound in a pocket formed by PB1 and PA close to the polymerase active site. This structure lays the basis for an atomic-level mechanistic understanding of the many functions of influenza polymerase, and opens new opportunities for anti-influenza drug design.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Pflug, Alexander -- Guilligay, Delphine -- Reich, Stefan -- Cusack, Stephen -- England -- Nature. 2014 Dec 18;516(7531):355-60. doi: 10.1038/nature14008. Epub 2014 Nov 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble Cedex 9, France [2] University Grenoble Alpes-Centre National de la Recherche Scientifique-EMBL Unit of Virus Host-Cell Interactions, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble Cedex 9, France.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25409142" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Crystallization ; DNA-Directed RNA Polymerases/*chemistry ; Influenza A virus/*enzymology ; Models, Molecular ; Promoter Regions, Genetic ; Protein Binding ; Protein Structure, Tertiary ; Protein Subunits/chemistry ; RNA, Viral/*chemistry
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  • 32
    Publication Date: 2014-02-28
    Description: Tripartite Tc toxin complexes of bacterial pathogens perforate the host membrane and translocate toxic enzymes into the host cell, including in humans. The underlying mechanism is complex but poorly understood. Here we report the first, to our knowledge, high-resolution structures of a TcA subunit in its prepore and pore state and of a complete 1.7 megadalton Tc complex. The structures reveal that, in addition to a translocation channel, TcA forms four receptor-binding sites and a neuraminidase-like region, which are important for its host specificity. pH-induced opening of the shell releases an entropic spring that drives the injection of the TcA channel into the membrane. Binding of TcB/TcC to TcA opens a gate formed by a six-bladed beta-propeller and results in a continuous protein translocation channel, whose architecture and properties suggest a novel mode of protein unfolding and translocation. Our results allow us to understand key steps of infections involving Tc toxins at the molecular level.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Meusch, Dominic -- Gatsogiannis, Christos -- Efremov, Rouslan G -- Lang, Alexander E -- Hofnagel, Oliver -- Vetter, Ingrid R -- Aktories, Klaus -- Raunser, Stefan -- England -- Nature. 2014 Apr 3;508(7494):61-5. doi: 10.1038/nature13015. Epub 2014 Feb 23.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Physical Biochemistry, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany [2]. ; Institut fur Experimentelle und Klinische Pharmakologie und Toxikologie, Albert-Ludwigs-Universitat Freiburg, 79104 Freiburg, Germany. ; Department of Physical Biochemistry, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany. ; Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany. ; 1] Institut fur Experimentelle und Klinische Pharmakologie und Toxikologie, Albert-Ludwigs-Universitat Freiburg, 79104 Freiburg, Germany [2] BIOSS Centre for Biological Signalling Studies, Albert-Ludwigs-Universitat Freiburg, 79104 Freiburg, Germany. ; 1] Department of Physical Biochemistry, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany [2] Institute of Chemistry and Biochemistry, Freie Universitat Berlin, Thielallee 63, 14195 Berlin, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24572368" target="_blank"〉PubMed〈/a〉
    Keywords: ADP Ribose Transferases/metabolism ; Bacterial Toxins/*chemistry/*metabolism ; Binding Sites ; Cell Membrane/metabolism ; Crystallography, X-Ray ; Host Specificity ; Hydrogen-Ion Concentration ; Models, Molecular ; Neuraminidase/chemistry ; Photorhabdus/*chemistry ; Porosity ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; Protein Transport ; Protein Unfolding ; Structure-Activity Relationship
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  • 33
    Publication Date: 2014-02-21
    Description: Hepatitis C virus (HCV) is a significant public health concern with approximately 160 million people infected worldwide. HCV infection often results in chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. No vaccine is available and current therapies are effective against some, but not all, genotypes. HCV is an enveloped virus with two surface glycoproteins (E1 and E2). E2 binds to the host cell through interactions with scavenger receptor class B type I (SR-BI) and CD81, and serves as a target for neutralizing antibodies. Little is known about the molecular mechanism that mediates cell entry and membrane fusion, although E2 is predicted to be a class II viral fusion protein. Here we describe the structure of the E2 core domain in complex with an antigen-binding fragment (Fab) at 2.4 A resolution. The E2 core has a compact, globular domain structure, consisting mostly of beta-strands and random coil with two small alpha-helices. The strands are arranged in two, perpendicular sheets (A and B), which are held together by an extensive hydrophobic core and disulphide bonds. Sheet A has an IgG-like fold that is commonly found in viral and cellular proteins, whereas sheet B represents a novel fold. Solution-based studies demonstrate that the full-length E2 ectodomain has a similar globular architecture and does not undergo significant conformational or oligomeric rearrangements on exposure to low pH. Thus, the IgG-like fold is the only feature that E2 shares with class II membrane fusion proteins. These results provide unprecedented insights into HCV entry and will assist in developing an HCV vaccine and new inhibitors.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4126800/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4126800/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Khan, Abdul Ghafoor -- Whidby, Jillian -- Miller, Matthew T -- Scarborough, Hannah -- Zatorski, Alexandra V -- Cygan, Alicja -- Price, Aryn A -- Yost, Samantha A -- Bohannon, Caitlin D -- Jacob, Joshy -- Grakoui, Arash -- Marcotrigiano, Joseph -- AI070101/AI/NIAID NIH HHS/ -- DK083356/DK/NIDDK NIH HHS/ -- P50 GM103368/GM/NIGMS NIH HHS/ -- P51 OD011132/OD/NIH HHS/ -- P51 RR000165/RR/NCRR NIH HHS/ -- R01 AI070101/AI/NIAID NIH HHS/ -- R01 AI080659/AI/NIAID NIH HHS/ -- R01 DK083356/DK/NIDDK NIH HHS/ -- RR-00165/RR/NCRR NIH HHS/ -- T32 AI007403/AI/NIAID NIH HHS/ -- T32 AI007610/AI/NIAID NIH HHS/ -- England -- Nature. 2014 May 15;509(7500):381-4. doi: 10.1038/nature13117. Epub 2014 Feb 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Center for Advanced Biotechnology and Medicine, Department of Chemistry and Chemical Biology, Rutgers University, 679 Hoes Lane West, Piscataway, New Jersey 08854, USA. ; Division of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, 100 Woodruff Circle, Atlanta, Georgia 30322, USA. ; 1] Division of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, 100 Woodruff Circle, Atlanta, Georgia 30322, USA [2] Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, 100 Woodruff Circle, Atlanta, Georgia 30322, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24553139" target="_blank"〉PubMed〈/a〉
    Keywords: Crystallography, X-Ray ; Disulfides/chemistry ; Hepacivirus/*chemistry/physiology ; Hydrogen-Ion Concentration ; Hydrophobic and Hydrophilic Interactions ; Immunoglobulin Fab Fragments/chemistry/metabolism ; Immunoglobulin G/chemistry ; Models, Molecular ; Protein Folding ; Protein Structure, Tertiary ; Scattering, Small Angle ; Surface Properties ; Viral Envelope Proteins/*chemistry/metabolism ; Viral Fusion Proteins ; Viral Hepatitis Vaccines ; Virus Internalization
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  • 34
    Publication Date: 2014-05-23
    Description: The glucose transporter GLUT1 catalyses facilitative diffusion of glucose into erythrocytes and is responsible for glucose supply to the brain and other organs. Dysfunctional mutations may lead to GLUT1 deficiency syndrome, whereas overexpression of GLUT1 is a prognostic indicator for cancer. Despite decades of investigation, the structure of GLUT1 remains unknown. Here we report the crystal structure of human GLUT1 at 3.2 A resolution. The full-length protein, which has a canonical major facilitator superfamily fold, is captured in an inward-open conformation. This structure allows accurate mapping and potential mechanistic interpretation of disease-associated mutations in GLUT1. Structure-based analysis of these mutations provides an insight into the alternating access mechanism of GLUT1 and other members of the sugar porter subfamily. Structural comparison of the uniporter GLUT1 with its bacterial homologue XylE, a proton-coupled xylose symporter, allows examination of the transport mechanisms of both passive facilitators and active transporters.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Deng, Dong -- Xu, Chao -- Sun, Pengcheng -- Wu, Jianping -- Yan, Chuangye -- Hu, Mingxu -- Yan, Nieng -- Howard Hughes Medical Institute/ -- England -- Nature. 2014 Jun 5;510(7503):121-5. doi: 10.1038/nature13306. Epub 2014 May 18.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] State Key Laboratory of Bio-membrane and Membrane Biotechnology, Tsinghua University, Beijing 100084, China [2] Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [3] Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China [4]. ; 1] State Key Laboratory of Bio-membrane and Membrane Biotechnology, Tsinghua University, Beijing 100084, China [2] Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [3]. ; 1] State Key Laboratory of Bio-membrane and Membrane Biotechnology, Tsinghua University, Beijing 100084, China [2] Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China. ; 1] State Key Laboratory of Bio-membrane and Membrane Biotechnology, Tsinghua University, Beijing 100084, China [2] Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [3] Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24847886" target="_blank"〉PubMed〈/a〉
    Keywords: Carbohydrate Metabolism, Inborn Errors/genetics ; Crystallography, X-Ray ; Escherichia coli Proteins ; Glucose Transporter Type 1/*chemistry/deficiency/genetics/metabolism ; Humans ; Ligands ; Models, Biological ; Models, Molecular ; Monosaccharide Transport Proteins/deficiency/genetics ; Mutation/genetics ; Protein Structure, Tertiary ; Structure-Activity Relationship ; Symporters
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  • 35
    Publication Date: 2014-09-12
    Description: Genetic equality between males and females is established by chromosome-wide dosage-compensation mechanisms. In the fruitfly Drosophila melanogaster, the dosage-compensation complex promotes twofold hypertranscription of the single male X-chromosome and is silenced in females by inhibition of the translation of msl2, which codes for the limiting component of the dosage-compensation complex. The female-specific protein Sex-lethal (Sxl) recruits Upstream-of-N-ras (Unr) to the 3' untranslated region of msl2 messenger RNA, preventing the engagement of the small ribosomal subunit. Here we report the 2.8 A crystal structure, NMR and small-angle X-ray and neutron scattering data of the ternary Sxl-Unr-msl2 ribonucleoprotein complex featuring unprecedented intertwined interactions of two Sxl RNA recognition motifs, a Unr cold-shock domain and RNA. Cooperative complex formation is associated with a 1,000-fold increase of RNA binding affinity for the Unr cold-shock domain and involves novel ternary interactions, as well as non-canonical RNA contacts by the alpha1 helix of Sxl RNA recognition motif 1. Our results suggest that repression of dosage compensation, necessary for female viability, is triggered by specific, cooperative molecular interactions that lock a ribonucleoprotein switch to regulate translation. The structure serves as a paradigm for how a combination of general and widespread RNA binding domains expands the code for specific single-stranded RNA recognition in the regulation of gene expression.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hennig, Janosch -- Militti, Cristina -- Popowicz, Grzegorz M -- Wang, Iren -- Sonntag, Miriam -- Geerlof, Arie -- Gabel, Frank -- Gebauer, Fatima -- Sattler, Michael -- England -- Nature. 2014 Nov 13;515(7526):287-90. doi: 10.1038/nature13693. Epub 2014 Sep 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Institute of Structural Biology, Helmholtz Zentrum Munchen, Ingolstadter Landstrasse 1, DE-85764, Germany [2] Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universitat Munchen, Lichtenbergstr. 4, DE-85747 Garching, Germany. ; 1] Centre for Genomic Regulation, Gene Regulation, Stem Cells and Cancer Programme, Dr Aiguader 88, 08003 Barcelona, Spain [2] Universisty Pompeu Fabra, Dr Aiguader 88, 08003 Barcelona, Spain. ; Institute of Structural Biology, Helmholtz Zentrum Munchen, Ingolstadter Landstrasse 1, DE-85764, Germany. ; 1] Universite Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France [2] Centre National de la Recherche Scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France [3] Commissariat a l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, F-38044 Grenoble, France [4] Institut Laue-Langevin, F-38042 Grenoble, France.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25209665" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Binding Sites ; Cell Line ; Cold-Shock Response ; Crystallography, X-Ray ; DNA-Binding Proteins/*chemistry/*metabolism ; Dosage Compensation, Genetic ; Drosophila Proteins/*chemistry/*metabolism ; Drosophila melanogaster/*chemistry/genetics ; Female ; Gene Expression Regulation ; Male ; Models, Molecular ; Neutron Diffraction ; Nuclear Magnetic Resonance, Biomolecular ; Nucleotide Motifs ; *Protein Biosynthesis ; Protein Structure, Tertiary ; RNA, Messenger/chemistry/*metabolism ; RNA-Binding Proteins/*chemistry/*metabolism ; Ribonucleoproteins/chemistry/metabolism ; Scattering, Small Angle ; Structure-Activity Relationship ; X-Ray Diffraction
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  • 36
    Publication Date: 2014-01-28
    Description: A well-balanced human diet includes a significant intake of non-starch polysaccharides, collectively termed 'dietary fibre', from the cell walls of diverse fruits and vegetables. Owing to the paucity of alimentary enzymes encoded by the human genome, our ability to derive energy from dietary fibre depends on the saccharification and fermentation of complex carbohydrates by the massive microbial community residing in our distal gut. The xyloglucans (XyGs) are a ubiquitous family of highly branched plant cell wall polysaccharides whose mechanism(s) of degradation in the human gut and consequent importance in nutrition have been unclear. Here we demonstrate that a single, complex gene locus in Bacteroides ovatus confers XyG catabolism in this common colonic symbiont. Through targeted gene disruption, biochemical analysis of all predicted glycoside hydrolases and carbohydrate-binding proteins, and three-dimensional structural determination of the vanguard endo-xyloglucanase, we reveal the molecular mechanisms through which XyGs are hydrolysed to component monosaccharides for further metabolism. We also observe that orthologous XyG utilization loci (XyGULs) serve as genetic markers of XyG catabolism in Bacteroidetes, that XyGULs are restricted to a limited number of phylogenetically diverse strains, and that XyGULs are ubiquitous in surveyed human metagenomes. Our findings reveal that the metabolism of even highly abundant components of dietary fibre may be mediated by niche species, which has immediate fundamental and practical implications for gut symbiont population ecology in the context of human diet, nutrition and health.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4282169/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4282169/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Larsbrink, Johan -- Rogers, Theresa E -- Hemsworth, Glyn R -- McKee, Lauren S -- Tauzin, Alexandra S -- Spadiut, Oliver -- Klinter, Stefan -- Pudlo, Nicholas A -- Urs, Karthik -- Koropatkin, Nicole M -- Creagh, A Louise -- Haynes, Charles A -- Kelly, Amelia G -- Cederholm, Stefan Nilsson -- Davies, Gideon J -- Martens, Eric C -- Brumer, Harry -- BB/I014802/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- DK084214/DK/NIDDK NIH HHS/ -- GM099513/GM/NIGMS NIH HHS/ -- K01 DK084214/DK/NIDDK NIH HHS/ -- R01 GM099513/GM/NIGMS NIH HHS/ -- England -- Nature. 2014 Feb 27;506(7489):498-502. doi: 10.1038/nature12907. Epub 2014 Jan 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Division of Glycoscience, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Centre, 106 91 Stockholm, Sweden [2]. ; 1] Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA [2]. ; 1] Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, UK [2]. ; 1] Division of Glycoscience, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Centre, 106 91 Stockholm, Sweden [2] Wallenberg Wood Science Center, Royal Institute of Technology (KTH), Teknikringen 56-58, 100 44 Stockholm, Sweden. ; Michael Smith Laboratories and Department of Chemistry, University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada. ; Division of Glycoscience, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Centre, 106 91 Stockholm, Sweden. ; Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA. ; Michael Smith Laboratories and Department of Chemical and Biological Engineering, University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada. ; Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, UK. ; 1] Division of Glycoscience, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Centre, 106 91 Stockholm, Sweden [2] Michael Smith Laboratories and Department of Chemistry, University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24463512" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Bacteroides/enzymology/*genetics/growth & development/*metabolism ; Carbohydrate Metabolism/genetics ; Carbohydrate Sequence ; Cell Wall/chemistry ; Crystallography, X-Ray ; Diet ; Dietary Fiber ; Evolution, Molecular ; Gastrointestinal Tract/*microbiology ; Genetic Loci/*genetics ; Glucans/chemistry/*metabolism ; Glycoside Hydrolases/chemistry/genetics/metabolism ; Humans ; Metagenome ; Models, Molecular ; Molecular Sequence Data ; Phylogeny ; Protein Structure, Tertiary ; Symbiosis ; Xylans/chemistry/*metabolism
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  • 37
    Publication Date: 2014-11-28
    Description: Human tumours typically harbour a remarkable number of somatic mutations. If presented on major histocompatibility complex class I molecules (MHCI), peptides containing these mutations could potentially be immunogenic as they should be recognized as 'non-self' neo-antigens by the adaptive immune system. Recent work has confirmed that mutant peptides can serve as T-cell epitopes. However, few mutant epitopes have been described because their discovery required the laborious screening of patient tumour-infiltrating lymphocytes for their ability to recognize antigen libraries constructed following tumour exome sequencing. We sought to simplify the discovery of immunogenic mutant peptides by characterizing their general properties. We developed an approach that combines whole-exome and transcriptome sequencing analysis with mass spectrometry to identify neo-epitopes in two widely used murine tumour models. Of the 〉1,300 amino acid changes identified, approximately 13% were predicted to bind MHCI, a small fraction of which were confirmed by mass spectrometry. The peptides were then structurally modelled bound to MHCI. Mutations that were solvent-exposed and therefore accessible to T-cell antigen receptors were predicted to be immunogenic. Vaccination of mice confirmed the approach, with each predicted immunogenic peptide yielding therapeutically active T-cell responses. The predictions also enabled the generation of peptide-MHCI dextramers that could be used to monitor the kinetics and distribution of the anti-tumour T-cell response before and after vaccination. These findings indicate that a suitable prediction algorithm may provide an approach for the pharmacodynamic monitoring of T-cell responses as well as for the development of personalized vaccines in cancer patients.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yadav, Mahesh -- Jhunjhunwala, Suchit -- Phung, Qui T -- Lupardus, Patrick -- Tanguay, Joshua -- Bumbaca, Stephanie -- Franci, Christian -- Cheung, Tommy K -- Fritsche, Jens -- Weinschenk, Toni -- Modrusan, Zora -- Mellman, Ira -- Lill, Jennie R -- Delamarre, Lelia -- England -- Nature. 2014 Nov 27;515(7528):572-6. doi: 10.1038/nature14001.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Genentech, South San Francisco, California 94080, USA. ; Immatics Biotechnologies GmbH, 72076 Tubingen, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25428506" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; CD8-Positive T-Lymphocytes/immunology ; Cancer Vaccines/immunology ; Cell Line, Tumor ; Exome/*genetics ; Female ; Gene Expression Profiling ; Immunity, Cellular/immunology ; Immunogenetic Phenomena/*genetics ; Immunoprecipitation ; *Mass Spectrometry ; Mice ; Mice, Inbred C57BL ; Models, Molecular ; *Mutation ; Neoplasms/*genetics/immunology ; Peptides/genetics ; Protein Structure, Tertiary
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  • 38
    Publication Date: 2014-10-21
    Description: Protein poly(ADP-ribosyl)ation (PARylation) has a role in diverse cellular processes such as DNA repair, transcription, Wnt signalling, and cell death. Recent studies have shown that PARylation can serve as a signal for the polyubiquitination and degradation of several crucial regulatory proteins, including Axin and 3BP2 (refs 7, 8, 9). The RING-type E3 ubiquitin ligase RNF146 (also known as Iduna) is responsible for PARylation-dependent ubiquitination (PARdU). Here we provide a structural basis for RNF146-catalysed PARdU and how PARdU specificity is achieved. First, we show that iso-ADP-ribose (iso-ADPr), the smallest internal poly(ADP-ribose) (PAR) structural unit, binds between the WWE and RING domains of RNF146 and functions as an allosteric signal that switches the RING domain from a catalytically inactive state to an active one. In the absence of PAR, the RING domain is unable to bind and activate a ubiquitin-conjugating enzyme (E2) efficiently. Binding of PAR or iso-ADPr induces a major conformational change that creates a functional RING structure. Thus, RNF146 represents a new mechanistic class of RING E3 ligases, the activities of which are regulated by non-covalent ligand binding, and that may provide a template for designing inducible protein-degradation systems. Second, we find that RNF146 directly interacts with the PAR polymerase tankyrase (TNKS). Disruption of the RNF146-TNKS interaction inhibits turnover of the substrate Axin in cells. Thus, both substrate PARylation and PARdU are catalysed by enzymes within the same protein complex, and PARdU substrate specificity may be primarily determined by the substrate-TNKS interaction. We propose that the maintenance of unliganded RNF146 in an inactive state may serve to maintain the stability of the RNF146-TNKS complex, which in turn regulates the homeostasis of PARdU activity in the cell.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4289021/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4289021/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉DaRosa, Paul A -- Wang, Zhizhi -- Jiang, Xiaomo -- Pruneda, Jonathan N -- Cong, Feng -- Klevit, Rachel E -- Xu, Wenqing -- R01 GM099766/GM/NIGMS NIH HHS/ -- T32 GM007270/GM/NIGMS NIH HHS/ -- T32 GM07270/GM/NIGMS NIH HHS/ -- England -- Nature. 2015 Jan 8;517(7533):223-6. doi: 10.1038/nature13826. Epub 2014 Oct 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA. ; Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA. ; Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, USA. ; Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25327252" target="_blank"〉PubMed〈/a〉
    Keywords: Adenosine Diphosphate Ribose/chemistry/metabolism ; Allosteric Regulation ; Animals ; Biocatalysis ; Crystallography, X-Ray ; Enzyme Activation ; Humans ; Ligands ; Mice ; Models, Molecular ; Poly Adenosine Diphosphate Ribose/chemistry/*metabolism ; Protein Binding ; *Protein Processing, Post-Translational ; Protein Structure, Tertiary ; Substrate Specificity ; Tankyrases/metabolism ; Ubiquitin-Conjugating Enzymes/chemistry/metabolism ; Ubiquitin-Protein Ligases/chemistry/*metabolism ; Ubiquitination
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  • 39
    Publication Date: 2014-11-11
    Description: The spindle assembly checkpoint (SAC) maintains genomic stability by delaying chromosome segregation until the last chromosome has attached to the mitotic spindle. The SAC prevents the anaphase promoting complex/cyclosome (APC/C) ubiquitin ligase from recognizing cyclin B and securin by catalysing the incorporation of the APC/C co-activator, CDC20, into a complex called the mitotic checkpoint complex (MCC). The SAC works through unattached kinetochores generating a diffusible 'wait anaphase' signal that inhibits the APC/C in the cytoplasm, but the nature of this signal remains a key unsolved problem. Moreover, the SAC and the APC/C are highly responsive to each other: the APC/C quickly targets cyclin B and securin once all the chromosomes attach in metaphase, but is rapidly inhibited should kinetochore attachment be perturbed. How this is achieved is also unknown. Here, we show that the MCC can inhibit a second CDC20 that has already bound and activated the APC/C. We show how the MCC inhibits active APC/C and that this is essential for the SAC. Moreover, this mechanism can prevent anaphase in the absence of kinetochore signalling. Thus, we propose that the diffusible 'wait anaphase' signal could be the MCC itself, and explain how reactivating the SAC can rapidly inhibit active APC/C.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4312099/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4312099/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Izawa, Daisuke -- Pines, Jonathon -- 092096/Wellcome Trust/United Kingdom -- 13959/Cancer Research UK/United Kingdom -- A13678/Cancer Research UK/United Kingdom -- A13959/Cancer Research UK/United Kingdom -- Cancer Research UK/United Kingdom -- England -- Nature. 2015 Jan 29;517(7536):631-4. doi: 10.1038/nature13911. Epub 2014 Nov 12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉The Gurdon Institute and Department of Zoology, Tennis Court Road, Cambridge CB2 1QN, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25383541" target="_blank"〉PubMed〈/a〉
    Keywords: Anaphase ; Anaphase-Promoting Complex-Cyclosome/*antagonists & inhibitors/metabolism ; Animals ; Cdc20 Proteins/*metabolism ; Cytoplasm/enzymology/metabolism ; HeLa Cells ; Humans ; M Phase Cell Cycle Checkpoints ; *Mitosis ; Multiprotein Complexes/*metabolism ; Protein Binding ; Protein Structure, Tertiary ; Protein-Serine-Threonine Kinases/chemistry/metabolism ; Spindle Apparatus/metabolism ; Substrate Specificity
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  • 40
    Publication Date: 2014-11-11
    Description: Biotin-dependent carboxylases are widely distributed in nature and have important functions in the metabolism of fatty acids, amino acids, carbohydrates, cholesterol and other compounds. Defective mutations in several of these enzymes have been linked to serious metabolic diseases in humans, and acetyl-CoA carboxylase is a target for drug discovery in the treatment of diabetes, cancer and other diseases. Here we report the identification and biochemical, structural and functional characterizations of a novel single-chain (120 kDa), multi-domain biotin-dependent carboxylase in bacteria. It has preference for long-chain acyl-CoA substrates, although it is also active towards short-chain and medium-chain acyl-CoAs, and we have named it long-chain acyl-CoA carboxylase. The holoenzyme is a homo-hexamer with molecular mass of 720 kDa. The 3.0 A crystal structure of the long-chain acyl-CoA carboxylase holoenzyme from Mycobacterium avium subspecies paratuberculosis revealed an architecture that is strikingly different from those of related biotin-dependent carboxylases. In addition, the domains of each monomer have no direct contact with each other. They are instead extensively swapped in the holoenzyme, such that one cycle of catalysis involves the participation of four monomers. Functional studies in Pseudomonas aeruginosa suggest that the enzyme is involved in the utilization of selected carbon and nitrogen sources.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4319993/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4319993/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Tran, Timothy H -- Hsiao, Yu-Shan -- Jo, Jeanyoung -- Chou, Chi-Yuan -- Dietrich, Lars E P -- Walz, Thomas -- Tong, Liang -- 1S10RR028832/RR/NCRR NIH HHS/ -- P01 GM062580/GM/NIGMS NIH HHS/ -- R01 AI103369/AI/NIAID NIH HHS/ -- R01AI103369/AI/NIAID NIH HHS/ -- R01DK067238/DK/NIDDK NIH HHS/ -- S10OD012018/OD/NIH HHS/ -- T32 GM008798/GM/NIGMS NIH HHS/ -- U54GM094597/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2015 Feb 5;518(7537):120-4. doi: 10.1038/nature13912. Epub 2014 Nov 10.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biological Sciences, Columbia University, New York, New York 10027, USA. ; Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA. ; 1] Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA [2] Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25383525" target="_blank"〉PubMed〈/a〉
    Keywords: Acyl Coenzyme A/metabolism ; Biocatalysis ; Biotin/metabolism ; Carbon/metabolism ; Carbon-Carbon Ligases/*chemistry/*metabolism/ultrastructure ; Cryoelectron Microscopy ; Crystallography, X-Ray ; Holoenzymes/chemistry/metabolism ; Models, Molecular ; Mycobacterium avium subsp. paratuberculosis/*enzymology ; Nitrogen/metabolism ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; Pseudomonas aeruginosa/enzymology/genetics/metabolism ; Structure-Activity Relationship
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  • 41
    Publication Date: 2014-12-18
    Description: The ryanodine receptors (RyRs) are high-conductance intracellular Ca(2+) channels that play a pivotal role in the excitation-contraction coupling of skeletal and cardiac muscles. RyRs are the largest known ion channels, with a homotetrameric organization and approximately 5,000 residues in each protomer. Here we report the structure of the rabbit RyR1 in complex with its modulator FKBP12 at an overall resolution of 3.8 A, determined by single-particle electron cryomicroscopy. Three previously uncharacterized domains, named central, handle and helical domains, display the armadillo repeat fold. These domains, together with the amino-terminal domain, constitute a network of superhelical scaffold for binding and propagation of conformational changes. The channel domain exhibits the voltage-gated ion channel superfamily fold with distinct features. A negative-charge-enriched hairpin loop connecting S5 and the pore helix is positioned above the entrance to the selectivity-filter vestibule. The four elongated S6 segments form a right-handed helical bundle that closes the pore at the cytoplasmic border of the membrane. Allosteric regulation of the pore by the cytoplasmic domains is mediated through extensive interactions between the central domains and the channel domain. These structural features explain high ion conductance by RyRs and the long-range allosteric regulation of channel activities.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4338550/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4338550/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yan, Zhen -- Bai, Xiao-chen -- Yan, Chuangye -- Wu, Jianping -- Li, Zhangqiang -- Xie, Tian -- Peng, Wei -- Yin, Chang-cheng -- Li, Xueming -- Scheres, Sjors H W -- Shi, Yigong -- Yan, Nieng -- MC_UP_A025_1013/Medical Research Council/United Kingdom -- England -- Nature. 2015 Jan 1;517(7532):50-5. doi: 10.1038/nature14063. Epub 2014 Dec 15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] State Key Laboratory of Bio-membrane and Membrane Biotechnology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [2] Ministry of Education Key Laboratory of Protein Science, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [3] Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China. ; MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK. ; 1] Ministry of Education Key Laboratory of Protein Science, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [2] Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China. ; 1] State Key Laboratory of Bio-membrane and Membrane Biotechnology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China [2] Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China. ; Department of Biophysics, the Health Science Center &Center for Protein Science, Peking University, Beijing 100191, China. ; Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25517095" target="_blank"〉PubMed〈/a〉
    Keywords: Algorithms ; Allosteric Regulation ; Animals ; Cryoelectron Microscopy ; Ion Channel Gating ; Models, Molecular ; Molecular Weight ; Protein Multimerization ; Protein Structure, Tertiary ; Rabbits ; Ryanodine Receptor Calcium Release Channel/*chemistry/metabolism/*ultrastructure ; Sarcoplasmic Reticulum/chemistry ; Tacrolimus Binding Protein 1A/chemistry/metabolism/ultrastructure ; Zinc Fingers
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  • 42
    Publication Date: 2013-05-03
    Description: DNA methylation is an epigenetic modification that has critical roles in gene silencing, development and genome integrity. In Arabidopsis, DNA methylation is established by DOMAINS REARRANGED METHYLTRANSFERASE 2 (DRM2) and targeted by 24-nucleotide small interfering RNAs (siRNAs) through a pathway termed RNA-directed DNA methylation (RdDM). This pathway requires two plant-specific RNA polymerases: Pol-IV, which functions to initiate siRNA biogenesis, and Pol-V, which functions to generate scaffold transcripts that recruit downstream RdDM factors. To understand the mechanisms controlling Pol-IV targeting we investigated the function of SAWADEE HOMEODOMAIN HOMOLOG 1 (SHH1), a Pol-IV-interacting protein. Here we show that SHH1 acts upstream in the RdDM pathway to enable siRNA production from a large subset of the most active RdDM targets, and that SHH1 is required for Pol-IV occupancy at these same loci. We also show that the SHH1 SAWADEE domain is a novel chromatin-binding module that adopts a unique tandem Tudor-like fold and functions as a dual lysine reader, probing for both unmethylated K4 and methylated K9 modifications on the histone 3 (H3) tail. Finally, we show that key residues within both lysine-binding pockets of SHH1 are required in vivo to maintain siRNA and DNA methylation levels as well as Pol-IV occupancy at RdDM targets, demonstrating a central role for methylated H3K9 binding in SHH1 function and providing the first insights into the mechanism of Pol-IV targeting. Given the parallels between methylation systems in plants and mammals, a further understanding of this early targeting step may aid our ability to control the expression of endogenous and newly introduced genes, which has broad implications for agriculture and gene therapy.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4119789/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4119789/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Law, Julie A -- Du, Jiamu -- Hale, Christopher J -- Feng, Suhua -- Krajewski, Krzysztof -- Palanca, Ana Marie S -- Strahl, Brian D -- Patel, Dinshaw J -- Jacobsen, Steven E -- GM60398/GM/NIGMS NIH HHS/ -- GM85394/GM/NIGMS NIH HHS/ -- R01 GM060398/GM/NIGMS NIH HHS/ -- R37 GM060398/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2013 Jun 20;498(7454):385-9. doi: 10.1038/nature12178. Epub 2013 May 1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23636332" target="_blank"〉PubMed〈/a〉
    Keywords: Arabidopsis/*enzymology/genetics/*metabolism ; Arabidopsis Proteins/chemistry/genetics/*metabolism ; Binding Sites/genetics ; Chromatin/chemistry/genetics/metabolism ; Crystallography, X-Ray ; DNA Methylation/*genetics ; DNA-Directed RNA Polymerases/genetics/*metabolism ; Epigenesis, Genetic/genetics ; Histones/chemistry/metabolism ; Homeodomain Proteins/chemistry/*metabolism ; Lysine/chemistry/metabolism ; Methyltransferases/genetics/metabolism ; Models, Molecular ; Mutation ; Protein Folding ; Protein Structure, Tertiary ; RNA, Small Interfering/biosynthesis/genetics/metabolism
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  • 43
    Publication Date: 2013-07-19
    Description: Structural analysis of class B G-protein-coupled receptors (GPCRs), cell-surface proteins that respond to peptide hormones, has been restricted to the amino-terminal extracellular domain, thus providing little understanding of the membrane-spanning signal transduction domain. The corticotropin-releasing factor receptor type 1 is a class B receptor which mediates the response to stress and has been considered a drug target for depression and anxiety. Here we report the crystal structure of the transmembrane domain of the human corticotropin-releasing factor receptor type 1 in complex with the small-molecule antagonist CP-376395. The structure provides detailed insight into the architecture of class B receptors. Atomic details of the interactions of the receptor with the non-peptide ligand that binds deep within the receptor are described. This structure provides a model for all class B GPCRs and may aid in the design of new small-molecule drugs for diseases of brain and metabolism.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hollenstein, Kaspar -- Kean, James -- Bortolato, Andrea -- Cheng, Robert K Y -- Dore, Andrew S -- Jazayeri, Ali -- Cooke, Robert M -- Weir, Malcolm -- Marshall, Fiona H -- England -- Nature. 2013 Jul 25;499(7459):438-43. doi: 10.1038/nature12357. Epub 2013 Jul 17.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Heptares Therapeutics Ltd, BioPark, Broadwater Road, Welwyn Garden City AL7 3AX, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23863939" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Amino Acid Sequence ; Aminopyridines/chemistry/metabolism/pharmacology ; Binding Sites ; Conserved Sequence ; Crystallography, X-Ray ; HEK293 Cells ; Humans ; Ligands ; Models, Molecular ; Molecular Sequence Data ; Protein Binding ; Protein Structure, Tertiary ; Receptors, Corticotropin-Releasing Hormone/antagonists & ; inhibitors/*chemistry/*classification/metabolism ; Receptors, Dopamine D3/antagonists & inhibitors/chemistry/classification
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  • 44
    Publication Date: 2013-05-24
    Description: Facilitates chromatin transcription (FACT) is a conserved histone chaperone that reorganizes nucleosomes and ensures chromatin integrity during DNA transcription, replication and repair. Key to the broad functions of FACT is its recognition of histones H2A-H2B (ref. 2). However, the structural basis for how histones H2A-H2B are recognized and how this integrates with the other functions of FACT, including the recognition of histones H3-H4 and other nuclear factors, is unknown. Here we reveal the crystal structure of the evolutionarily conserved FACT chaperone domain Spt16M from Chaetomium thermophilum, in complex with the H2A-H2B heterodimer. A novel 'U-turn' motif scaffolded onto a Rtt106-like module embraces the alpha1 helix of H2B. Biochemical and in vivo assays validate the structure and dissect the contribution of histone tails and H3-H4 towards Spt16M binding. Furthermore, we report the structure of the FACT heterodimerization domain that connects FACT to replicative polymerases. Our results show that Spt16M makes several interactions with histones, which we suggest allow the module to invade the nucleosome gradually and block the strongest interaction of H2B with DNA. FACT would thus enhance 'nucleosome breathing' by re-organizing the first 30 base pairs of nucleosomal histone-DNA contacts. Our snapshot of the engagement of the chaperone with H2A-H2B and the structures of all globular FACT domains enable the high-resolution analysis of the vital chaperoning functions of FACT, shedding light on how the complex promotes the activity of enzymes that require nucleosome reorganization.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hondele, Maria -- Stuwe, Tobias -- Hassler, Markus -- Halbach, Felix -- Bowman, Andrew -- Zhang, Elisa T -- Nijmeijer, Bianca -- Kotthoff, Christiane -- Rybin, Vladimir -- Amlacher, Stefan -- Hurt, Ed -- Ladurner, Andreas G -- Howard Hughes Medical Institute/ -- England -- Nature. 2013 Jul 4;499(7456):111-4. doi: 10.1038/nature12242. Epub 2013 May 22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiological Chemistry, Butenandt Institute and LMU Biomedical Center, Faculty of Medicine, Ludwig Maximilians University of Munich, Butenandtstrasse 5, 81377 Munich, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23698368" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Chaetomium/*chemistry ; Conserved Sequence ; Crystallography, X-Ray ; DNA/chemistry/metabolism ; DNA Replication ; Fungal Proteins/*chemistry/*metabolism ; Histones/chemistry/*metabolism ; Hydrophobic and Hydrophilic Interactions ; Models, Molecular ; Molecular Chaperones/*chemistry/*metabolism ; Nucleosomes/chemistry/metabolism ; Protein Binding ; Protein Multimerization ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Substrate Specificity
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  • 45
    Publication Date: 2013-10-05
    Description: Excitatory amino acid transporters (EAATs) are secondary transport proteins that mediate the uptake of glutamate and other amino acids. EAATs fulfil an important role in neuronal signal transmission by clearing the excitatory neurotransmitters from the synaptic cleft after depolarization of the postsynaptic neuron. An intensively studied model system for understanding the transport mechanism of EAATs is the archaeal aspartate transporter GltPh. Each subunit in the homotrimeric GltPh supports the coupled translocation of one aspartate molecule and three Na(+) ions as well as an uncoupled flux of Cl(-) ions. Recent crystal structures of GltPh revealed three possible conformations for the subunits, but it is unclear whether the motions of individual subunits are coordinated to support transport. Here, we report the direct observation of conformational dynamics in individual GltPh trimers embedded in the membrane by applying single-molecule fluorescence resonance energy transfer (FRET). By analysing the transporters in a lipid bilayer instead of commonly used detergent micelles, we achieve conditions that approximate the physiologically relevant ones. From the kinetics of FRET level transitions we conclude that the three GltPh subunits undergo conformational changes stochastically and independently of each other.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Erkens, Guus B -- Hanelt, Inga -- Goudsmits, Joris M H -- Slotboom, Dirk Jan -- van Oijen, Antoine M -- England -- Nature. 2013 Oct 3;502(7469):119-23. doi: 10.1038/nature12538.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24091978" target="_blank"〉PubMed〈/a〉
    Keywords: Aspartic Acid/*chemistry/*metabolism ; Fluorescence Resonance Energy Transfer ; Glutamate Plasma Membrane Transport Proteins/*chemistry/metabolism ; Lipid Bilayers/metabolism ; *Models, Molecular ; Protein Structure, Tertiary ; Pyrococcus horikoshii/chemistry/metabolism ; Sodium/*chemistry
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  • 46
    Publication Date: 2013-12-07
    Description: Transient receptor potential (TRP) channels are polymodal signal detectors that respond to a wide range of physical and chemical stimuli. Elucidating how these channels integrate and convert physiological signals into channel opening is essential to understanding how they regulate cell excitability under normal and pathophysiological conditions. Here we exploit pharmacological probes (a peptide toxin and small vanilloid agonists) to determine structures of two activated states of the capsaicin receptor, TRPV1. A domain (consisting of transmembrane segments 1-4) that moves during activation of voltage-gated channels remains stationary in TRPV1, highlighting differences in gating mechanisms for these structurally related channel superfamilies. TRPV1 opening is associated with major structural rearrangements in the outer pore, including the pore helix and selectivity filter, as well as pronounced dilation of a hydrophobic constriction at the lower gate, suggesting a dual gating mechanism. Allosteric coupling between upper and lower gates may account for rich physiological modulation exhibited by TRPV1 and other TRP channels.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4023639/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4023639/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Cao, Erhu -- Liao, Maofu -- Cheng, Yifan -- Julius, David -- R01 GM098672/GM/NIGMS NIH HHS/ -- R01 NS047723/NS/NINDS NIH HHS/ -- R01 NS065071/NS/NINDS NIH HHS/ -- R01GM098672/GM/NIGMS NIH HHS/ -- R01NS047723/NS/NINDS NIH HHS/ -- R01NS065071/NS/NINDS NIH HHS/ -- S10 RR026814/RR/NCRR NIH HHS/ -- S10RR026814/RR/NCRR NIH HHS/ -- England -- Nature. 2013 Dec 5;504(7478):113-8. doi: 10.1038/nature12823.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Physiology, University of California, San Francisco, California 94158-2517, USA [2].〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24305161" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Models, Molecular ; Mutation ; Protein Structure, Tertiary ; Rats ; TRPV Cation Channels/*chemistry/genetics/*physiology
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  • 47
    Publication Date: 2013-08-21
    Description: The tumour necrosis factor (TNF) family is crucial for immune homeostasis, cell death and inflammation. These cytokines are recognized by members of the TNF receptor (TNFR) family of death receptors, including TNFR1 and TNFR2, and FAS and TNF-related apoptosis-inducing ligand (TRAIL) receptors. Death receptor signalling requires death-domain-mediated homotypic/heterotypic interactions between the receptor and its downstream adaptors, including TNFR1-associated death domain protein (TRADD) and FAS-associated death domain protein (FADD). Here we discover that death domains in several proteins, including TRADD, FADD, RIPK1 and TNFR1, were directly inactivated by NleB, an enteropathogenic Escherichia coli (EPEC) type III secretion system effector known to inhibit host nuclear factor-kappaB (NF-kappaB) signalling. NleB contained an unprecedented N-acetylglucosamine (GlcNAc) transferase activity that specifically modified a conserved arginine in these death domains (Arg 235 in the TRADD death domain). NleB GlcNAcylation (the addition of GlcNAc onto a protein side chain) of death domains blocked homotypic/heterotypic death domain interactions and assembly of the oligomeric TNFR1 complex, thereby disrupting TNF signalling in EPEC-infected cells, including NF-kappaB signalling, apoptosis and necroptosis. Type-III-delivered NleB also blocked FAS ligand and TRAIL-induced cell death by preventing formation of a FADD-mediated death-inducing signalling complex (DISC). The arginine GlcNAc transferase activity of NleB was required for bacterial colonization in the mouse model of EPEC infection. The mechanism of action of NleB represents a new model by which bacteria counteract host defences, and also a previously unappreciated post-translational modification.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Li, Shan -- Zhang, Li -- Yao, Qing -- Li, Lin -- Dong, Na -- Rong, Jie -- Gao, Wenqing -- Ding, Xiaojun -- Sun, Liming -- Chen, Xing -- Chen, She -- Shao, Feng -- Howard Hughes Medical Institute/ -- England -- Nature. 2013 Sep 12;501(7466):242-6. doi: 10.1038/nature12436. Epub 2013 Aug 18.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉College of Biological Sciences, China Agricultural University, Beijing 100094, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23955153" target="_blank"〉PubMed〈/a〉
    Keywords: Acylation ; Animals ; Antigens, CD95/metabolism ; Apoptosis ; Arginine/*metabolism ; Death Domain Receptor Signaling Adaptor Proteins/metabolism ; Disease Models, Animal ; Enteropathogenic Escherichia coli/*metabolism/pathogenicity ; Escherichia coli Infections/metabolism/microbiology/pathology ; Escherichia coli Proteins/*metabolism ; Fas-Associated Death Domain Protein/chemistry/metabolism ; HeLa Cells ; Humans ; Male ; Mice ; Mice, Inbred C57BL ; Multiprotein Complexes/chemistry/metabolism ; N-Acetylglucosaminyltransferases/*metabolism ; NF-kappa B/metabolism ; Protein Biosynthesis ; Protein Structure, Tertiary ; Receptor-Interacting Protein Serine-Threonine Kinases/chemistry/metabolism ; Receptors, Tumor Necrosis Factor, Type I/chemistry/metabolism ; *Signal Transduction ; TNF Receptor-Associated Death Domain Protein/*chemistry/*metabolism ; TNF-Related Apoptosis-Inducing Ligand/metabolism ; Tumor Necrosis Factor-alpha/metabolism ; Virulence ; Virulence Factors/*metabolism
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  • 48
    Publication Date: 2013-03-19
    Description: The cryptochrome (CRY) flavoproteins act as blue-light receptors in plants and insects, but perform light-independent functions at the core of the mammalian circadian clock. To drive clock oscillations, mammalian CRYs associate with the Period proteins (PERs) and together inhibit the transcription of their own genes. The SCF(FBXL3) ubiquitin ligase complex controls this negative feedback loop by promoting CRY ubiquitination and degradation. However, the molecular mechanisms of their interactions and the functional role of flavin adenine dinucleotide (FAD) binding in CRYs remain poorly understood. Here we report crystal structures of mammalian CRY2 in its apo, FAD-bound and FBXL3-SKP1-complexed forms. Distinct from other cryptochromes of known structures, mammalian CRY2 binds FAD dynamically with an open cofactor pocket. Notably, the F-box protein FBXL3 captures CRY2 by simultaneously occupying its FAD-binding pocket with a conserved carboxy-terminal tail and burying its PER-binding interface. This novel F-box-protein-substrate bipartite interaction is susceptible to disruption by both FAD and PERs, suggesting a new avenue for pharmacological targeting of the complex and a multifaceted regulatory mechanism of CRY ubiquitination.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3618506/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3618506/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Xing, Weiman -- Busino, Luca -- Hinds, Thomas R -- Marionni, Samuel T -- Saifee, Nabiha H -- Bush, Matthew F -- Pagano, Michele -- Zheng, Ning -- 5T32-HL007151/HL/NHLBI NIH HHS/ -- K99 CA166181/CA/NCI NIH HHS/ -- R01 GM057587/GM/NIGMS NIH HHS/ -- R01-CA107134/CA/NCI NIH HHS/ -- R01-GM057587/GM/NIGMS NIH HHS/ -- R21-CA161108/CA/NCI NIH HHS/ -- R37 CA076584/CA/NCI NIH HHS/ -- R37-CA-076584/CA/NCI NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2013 Apr 4;496(7443):64-8. doi: 10.1038/nature11964. Epub 2013 Mar 17.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23503662" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Apoproteins/chemistry/metabolism ; Binding Sites ; Cryptochromes/chemistry/*metabolism ; Crystallography, X-Ray ; Deoxyribodipyrimidine Photo-Lyase/chemistry ; Drosophila melanogaster/chemistry ; F-Box Proteins/chemistry/*metabolism ; Flavin-Adenine Dinucleotide/metabolism ; Humans ; Hydrophobic and Hydrophilic Interactions ; Mice ; Models, Molecular ; Protein Structure, Tertiary ; S-Phase Kinase-Associated Proteins/chemistry/metabolism ; SKP Cullin F-Box Protein Ligases/chemistry/*metabolism ; Substrate Specificity
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  • 49
    Publication Date: 2013-12-07
    Description: Transient receptor potential (TRP) channels are sensors for a wide range of cellular and environmental signals, but elucidating how these channels respond to physical and chemical stimuli has been hampered by a lack of detailed structural information. Here we exploit advances in electron cryo-microscopy to determine the structure of a mammalian TRP channel, TRPV1, at 3.4 A resolution, breaking the side-chain resolution barrier for membrane proteins without crystallization. Like voltage-gated channels, TRPV1 exhibits four-fold symmetry around a central ion pathway formed by transmembrane segments 5-6 (S5-S6) and the intervening pore loop, which is flanked by S1-S4 voltage-sensor-like domains. TRPV1 has a wide extracellular 'mouth' with a short selectivity filter. The conserved 'TRP domain' interacts with the S4-S5 linker, consistent with its contribution to allosteric modulation. Subunit organization is facilitated by interactions among cytoplasmic domains, including amino-terminal ankyrin repeats. These observations provide a structural blueprint for understanding unique aspects of TRP channel function.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4078027/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4078027/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Liao, Maofu -- Cao, Erhu -- Julius, David -- Cheng, Yifan -- R01 GM098672/GM/NIGMS NIH HHS/ -- R01 NS047723/NS/NINDS NIH HHS/ -- R01 NS065071/NS/NINDS NIH HHS/ -- R01GM098672/GM/NIGMS NIH HHS/ -- R01NS047723/NS/NINDS NIH HHS/ -- R01NS065071/NS/NINDS NIH HHS/ -- S10RR026814/RR/NCRR NIH HHS/ -- England -- Nature. 2013 Dec 5;504(7478):107-12. doi: 10.1038/nature12822.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158-2517, USA [2].〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24305160" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Ankyrin Repeat ; *Cryoelectron Microscopy ; HEK293 Cells ; Humans ; *Models, Molecular ; Protein Structure, Tertiary ; Rats ; TRPV Cation Channels/*chemistry
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  • 50
    Publication Date: 2013-06-14
    Description: 53BP1 (also called TP53BP1) is a chromatin-associated factor that promotes immunoglobulin class switching and DNA double-strand-break (DSB) repair by non-homologous end joining. To accomplish its function in DNA repair, 53BP1 accumulates at DSB sites downstream of the RNF168 ubiquitin ligase. How ubiquitin recruits 53BP1 to break sites remains unknown as its relocalization involves recognition of histone H4 Lys 20 (H4K20) methylation by its Tudor domain. Here we elucidate how vertebrate 53BP1 is recruited to the chromatin that flanks DSB sites. We show that 53BP1 recognizes mononucleosomes containing dimethylated H4K20 (H4K20me2) and H2A ubiquitinated on Lys 15 (H2AK15ub), the latter being a product of RNF168 action on chromatin. 53BP1 binds to nucleosomes minimally as a dimer using its previously characterized methyl-lysine-binding Tudor domain and a carboxy-terminal extension, termed the ubiquitination-dependent recruitment (UDR) motif, which interacts with the epitope formed by H2AK15ub and its surrounding residues on the H2A tail. 53BP1 is therefore a bivalent histone modification reader that recognizes a histone 'code' produced by DSB signalling.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3955401/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3955401/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Fradet-Turcotte, Amelie -- Canny, Marella D -- Escribano-Diaz, Cristina -- Orthwein, Alexandre -- Leung, Charles C Y -- Huang, Hao -- Landry, Marie-Claude -- Kitevski-LeBlanc, Julianne -- Noordermeer, Sylvie M -- Sicheri, Frank -- Durocher, Daniel -- 84297-1/Canadian Institutes of Health Research/Canada -- 84297-2/Canadian Institutes of Health Research/Canada -- MOP84297/Canadian Institutes of Health Research/Canada -- England -- Nature. 2013 Jul 4;499(7456):50-4. doi: 10.1038/nature12318. Epub 2013 Jun 12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23760478" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Amino Acid Sequence ; Animals ; Cell Cycle Proteins/chemistry/metabolism ; Cell Line ; Chromosomal Proteins, Non-Histone/chemistry/deficiency/genetics ; DNA Breaks, Double-Stranded ; *DNA Damage ; DNA-Binding Proteins/chemistry/deficiency/genetics ; Female ; Histones/*chemistry/*metabolism ; Humans ; Intracellular Signaling Peptides and ; Proteins/chemistry/deficiency/genetics/*metabolism ; Lysine/*metabolism ; Male ; Mice ; Molecular Sequence Data ; Mutant Proteins/chemistry/metabolism ; Nuclear Proteins/chemistry/metabolism ; Nucleosomes/chemistry/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Schizosaccharomyces ; Schizosaccharomyces pombe Proteins/chemistry/metabolism ; Signal Transduction ; Ubiquitin/*metabolism ; *Ubiquitination
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  • 51
    Publication Date: 2013-05-31
    Description: Retroviral capsid proteins are conserved structurally but assemble into different morphologies. The mature human immunodeficiency virus-1 (HIV-1) capsid is best described by a 'fullerene cone' model, in which hexamers of the capsid protein are linked to form a hexagonal surface lattice that is closed by incorporating 12 capsid-protein pentamers. HIV-1 capsid protein contains an amino-terminal domain (NTD) comprising seven alpha-helices and a beta-hairpin, a carboxy-terminal domain (CTD) comprising four alpha-helices, and a flexible linker with a 310-helix connecting the two structural domains. Structures of the capsid-protein assembly units have been determined by X-ray crystallography; however, structural information regarding the assembled capsid and the contacts between the assembly units is incomplete. Here we report the cryo-electron microscopy structure of a tubular HIV-1 capsid-protein assembly at 8 A resolution and the three-dimensional structure of a native HIV-1 core by cryo-electron tomography. The structure of the tubular assembly shows, at the three-fold interface, a three-helix bundle with critical hydrophobic interactions. Mutagenesis studies confirm that hydrophobic residues in the centre of the three-helix bundle are crucial for capsid assembly and stability, and for viral infectivity. The cryo-electron-microscopy structures enable modelling by large-scale molecular dynamics simulation, resulting in all-atom models for the hexamer-of-hexamer and pentamer-of-hexamer elements as well as for the entire capsid. Incorporation of pentamers results in closer trimer contacts and induces acute surface curvature. The complete atomic HIV-1 capsid model provides a platform for further studies of capsid function and for targeted pharmacological intervention.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3729984/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3729984/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zhao, Gongpu -- Perilla, Juan R -- Yufenyuy, Ernest L -- Meng, Xin -- Chen, Bo -- Ning, Jiying -- Ahn, Jinwoo -- Gronenborn, Angela M -- Schulten, Klaus -- Aiken, Christopher -- Zhang, Peijun -- GM082251/GM/NIGMS NIH HHS/ -- GM085043/GM/NIGMS NIH HHS/ -- GM104601/GM/NIGMS NIH HHS/ -- P41 GM104601/GM/NIGMS NIH HHS/ -- P50 GM082251/GM/NIGMS NIH HHS/ -- R01 GM085043/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 May 30;497(7451):643-6. doi: 10.1038/nature12162.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23719463" target="_blank"〉PubMed〈/a〉
    Keywords: Capsid/*chemistry/*ultrastructure ; Capsid Proteins/chemistry/ultrastructure ; Cryoelectron Microscopy ; HIV-1/*chemistry/*ultrastructure ; Human Immunodeficiency Virus Proteins/chemistry/ultrastructure ; Hydrophobic and Hydrophilic Interactions ; *Molecular Dynamics Simulation ; Protein Multimerization ; Protein Structure, Secondary ; Protein Structure, Tertiary
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  • 52
    Publication Date: 2013-03-22
    Description: Macrophages consist of at least two subgroups, M1 and M2 (refs 1-3). Whereas M1 macrophages are proinflammatory and have a central role in host defence against bacterial and viral infections, M2 macrophages are associated with responses to anti-inflammatory reactions, helminth infection, tissue remodelling, fibrosis and tumour progression. Trib1 is an adaptor protein involved in protein degradation by interacting with COP1 ubiquitin ligase. Genome-wide association studies in humans have implicated TRIB1 in lipid metabolism. Here we show that Trib1 is critical for the differentiation of F4/80(+)MR(+) tissue-resident macrophages--that share characteristics with M2 macrophages (which we term M2-like macrophages)--and eosinophils but not for the differentiation of M1 myeloid cells. Trib1 deficiency results in a severe reduction of M2-like macrophages in various organs, including bone marrow, spleen, lung and adipose tissues. Aberrant expression of C/EBPalpha in Trib1-deficient bone marrow cells is responsible for the defects in macrophage differentiation. Unexpectedly, mice lacking Trib1 in haematopoietic cells show diminished adipose tissue mass accompanied by evidence of increased lipolysis, even when fed a normal diet. Supplementation of M2-like macrophages rescues the pathophysiology, indicating that a lack of these macrophages is the cause of lipolysis. In response to a high-fat diet, mice lacking Trib1 in haematopoietic cells develop hypertriglyceridaemia and insulin resistance, together with increased proinflammatory cytokine gene induction. Collectively, these results demonstrate that Trib1 is critical for adipose tissue maintenance and suppression of metabolic disorders by controlling the differentiation of tissue-resident M2-like macrophages.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Satoh, Takashi -- Kidoya, Hiroyasu -- Naito, Hisamichi -- Yamamoto, Masahiro -- Takemura, Naoki -- Nakagawa, Katsuhiro -- Yoshioka, Yoshichika -- Morii, Eiichi -- Takakura, Nobuyuki -- Takeuchi, Osamu -- Akira, Shizuo -- P01 AI070167/AI/NIAID NIH HHS/ -- England -- Nature. 2013 Mar 28;495(7442):524-8. doi: 10.1038/nature11930. Epub 2013 Mar 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Host Defense, WPI Immunology Frontier Research Center, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23515163" target="_blank"〉PubMed〈/a〉
    Keywords: Adipose Tissue/*cytology/metabolism/pathology ; Animals ; Bone Marrow Cells/cytology/metabolism ; CCAAT-Enhancer-Binding Protein-alpha/metabolism ; Cell Count ; Cell Cycle Proteins/deficiency/genetics/metabolism ; *Cell Differentiation ; Cytokines/genetics ; Diet, High-Fat/adverse effects ; Eosinophils/cytology/metabolism ; Female ; Hypertriglyceridemia/chemically induced/genetics ; Inflammation Mediators/metabolism ; Insulin Resistance/genetics ; Intracellular Signaling Peptides and ; Proteins/chemistry/deficiency/genetics/*metabolism ; Lipodystrophy/chemically induced/metabolism/pathology ; Lipolysis ; Lung/cytology ; Macrophages/classification/*cytology/*metabolism ; Male ; Mice ; Neutrophils/cytology/metabolism ; Organ Specificity ; Protein Structure, Tertiary ; Protein-Serine-Threonine Kinases/*antagonists & ; inhibitors/chemistry/deficiency/genetics/metabolism ; Spleen/cytology ; Ubiquitin/metabolism
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  • 53
    Publication Date: 2013-10-29
    Description: Pentatricopeptide repeat (PPR) proteins represent a large family of sequence-specific RNA-binding proteins that are involved in multiple aspects of RNA metabolism. PPR proteins, which are found in exceptionally large numbers in the mitochondria and chloroplasts of terrestrial plants, recognize single-stranded RNA (ssRNA) in a modular fashion. The maize chloroplast protein PPR10 binds to two similar RNA sequences from the ATPI-ATPH and PSAJ-RPL33 intergenic regions, referred to as ATPH and PSAJ, respectively. By protecting the target RNA elements from 5' or 3' exonucleases, PPR10 defines the corresponding 5' and 3' messenger RNA termini. Despite rigorous functional characterizations, the structural basis of sequence-specific ssRNA recognition by PPR proteins remains to be elucidated. Here we report the crystal structures of PPR10 in RNA-free and RNA-bound states at resolutions of 2.85 and 2.45 A, respectively. In the absence of RNA binding, the nineteen repeats of PPR10 are assembled into a right-handed superhelical spiral. PPR10 forms an antiparallel, intertwined homodimer and exhibits considerable conformational changes upon binding to its target ssRNA, an 18-nucleotide PSAJ element. Six nucleotides of PSAJ are specifically recognized by six corresponding PPR10 repeats following the predicted code. The molecular basis for the specific and modular recognition of RNA bases A, G and U is revealed. The structural elucidation of RNA recognition by PPR proteins provides an important framework for potential biotechnological applications of PPR proteins in RNA-related research areas.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yin, Ping -- Li, Quanxiu -- Yan, Chuangye -- Liu, Ying -- Liu, Junjie -- Yu, Feng -- Wang, Zheng -- Long, Jiafu -- He, Jianhua -- Wang, Hong-Wei -- Wang, Jiawei -- Zhu, Jian-Kang -- Shi, Yigong -- Yan, Nieng -- Howard Hughes Medical Institute/ -- England -- Nature. 2013 Dec 5;504(7478):168-71. doi: 10.1038/nature12651. Epub 2013 Oct 27.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] State Key Laboratory of Bio-membrane and Membrane Biotechnology, Tsinghua University, Beijing 100084, China [2] Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China [3].〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24162847" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Crystallography, X-Ray ; *Models, Molecular ; Plant Proteins/*chemistry/genetics/*metabolism ; Protein Binding ; Protein Structure, Tertiary ; RNA/chemistry/*metabolism ; Zea mays/*chemistry/genetics/metabolism
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  • 54
    Publication Date: 2013-01-22
    Description: In various cellular membrane systems, vacuolar ATPases (V-ATPases) function as proton pumps, which are involved in many processes such as bone resorption and cancer metastasis, and these membrane proteins represent attractive drug targets for osteoporosis and cancer. The hydrophilic V(1) portion is known as a rotary motor, in which a central axis DF complex rotates inside a hexagonally arranged catalytic A(3)B(3) complex using ATP hydrolysis energy, but the molecular mechanism is not well defined owing to a lack of high-resolution structural information. We previously reported on the in vitro expression, purification and reconstitution of Enterococcus hirae V(1)-ATPase from the A(3)B(3) and DF complexes. Here we report the asymmetric structures of the nucleotide-free (2.8 A) and nucleotide-bound (3.4 A) A(3)B(3) complex that demonstrate conformational changes induced by nucleotide binding, suggesting a binding order in the right-handed rotational orientation in a cooperative manner. The crystal structures of the nucleotide-free (2.2 A) and nucleotide-bound (2.7 A) V(1)-ATPase are also reported. The more tightly packed nucleotide-binding site seems to be induced by DF binding, and ATP hydrolysis seems to be stimulated by the approach of a conserved arginine residue. To our knowledge, these asymmetric structures represent the first high-resolution view of the rotational mechanism of V(1)-ATPase.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Arai, Satoshi -- Saijo, Shinya -- Suzuki, Kano -- Mizutani, Kenji -- Kakinuma, Yoshimi -- Ishizuka-Katsura, Yoshiko -- Ohsawa, Noboru -- Terada, Takaho -- Shirouzu, Mikako -- Yokoyama, Shigeyuki -- Iwata, So -- Yamato, Ichiro -- Murata, Takeshi -- England -- Nature. 2013 Jan 31;493(7434):703-7. doi: 10.1038/nature11778. Epub 2013 Jan 13.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23334411" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Crystallization ; Enterococcus/*enzymology/genetics ; *Models, Molecular ; Mutation ; Nucleotides/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Protein Subunits ; Rotation ; Vacuolar Proton-Translocating ATPases/*chemistry/genetics
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  • 55
    Publication Date: 2013-01-29
    Description: The active centre of the spliceosome consists of an intricate network formed by U5, U2 and U6 small nuclear RNAs, and a pre-messenger-RNA substrate. Prp8, a component of the U5 small nuclear ribonucleoprotein particle, crosslinks extensively with this RNA catalytic core. Here we present the crystal structure of yeast Prp8 (residues 885-2413) in complex with Aar2, a U5 small nuclear ribonucleoprotein particle assembly factor. The structure reveals tightly associated domains of Prp8 resembling a bacterial group II intron reverse transcriptase and a type II restriction endonuclease. Suppressors of splice-site mutations, and an intron branch-point crosslink, map to a large cavity formed by the reverse transcriptase thumb, and the endonuclease-like and RNaseH-like domains. This cavity is large enough to accommodate the catalytic core of group II intron RNA. The structure provides crucial insights into the architecture of the spliceosome active site, and reinforces the notion that nuclear pre-mRNA splicing and group II intron splicing have a common origin.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3672837/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3672837/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Galej, Wojciech P -- Oubridge, Chris -- Newman, Andrew J -- Nagai, Kiyoshi -- MC_U105184330/Medical Research Council/United Kingdom -- U.1051.04.016(78933)/Medical Research Council/United Kingdom -- Medical Research Council/United Kingdom -- England -- Nature. 2013 Jan 31;493(7434):638-43. doi: 10.1038/nature11843. Epub 2013 Jan 23.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23354046" target="_blank"〉PubMed〈/a〉
    Keywords: Catalytic Domain ; *Models, Molecular ; Nuclear Proteins/chemistry/metabolism ; Protein Structure, Tertiary ; Ribonucleoprotein, U4-U6 Small Nuclear/*chemistry/genetics ; Ribonucleoprotein, U5 Small Nuclear/*chemistry/genetics ; Saccharomyces cerevisiae/*chemistry/genetics ; Saccharomyces cerevisiae Proteins/*chemistry/genetics/metabolism ; Spliceosomes/*chemistry
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  • 56
    Publication Date: 2013-05-03
    Description: The smoothened (SMO) receptor, a key signal transducer in the hedgehog signalling pathway, is responsible for the maintenance of normal embryonic development and is implicated in carcinogenesis. It is classified as a class frizzled (class F) G-protein-coupled receptor (GPCR), although the canonical hedgehog signalling pathway involves the GLI transcription factors and the sequence similarity with class A GPCRs is less than 10%. Here we report the crystal structure of the transmembrane domain of the human SMO receptor bound to the small-molecule antagonist LY2940680 at 2.5 A resolution. Although the SMO receptor shares the seven-transmembrane helical fold, most of the conserved motifs for class A GPCRs are absent, and the structure reveals an unusually complex arrangement of long extracellular loops stabilized by four disulphide bonds. The ligand binds at the extracellular end of the seven-transmembrane-helix bundle and forms extensive contacts with the loops.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3657389/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3657389/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wang, Chong -- Wu, Huixian -- Katritch, Vsevolod -- Han, Gye Won -- Huang, Xi-Ping -- Liu, Wei -- Siu, Fai Yiu -- Roth, Bryan L -- Cherezov, Vadim -- Stevens, Raymond C -- F32 DK088392/DK/NIDDK NIH HHS/ -- P50 GM073197/GM/NIGMS NIH HHS/ -- R01 DA017204/DA/NIDA NIH HHS/ -- R01 DA027170/DA/NIDA NIH HHS/ -- R01 DA27170/DA/NIDA NIH HHS/ -- R01 MH061887/MH/NIMH NIH HHS/ -- R01MH61887/MH/NIMH NIH HHS/ -- U19 MH082441/MH/NIMH NIH HHS/ -- U19 MH82441/MH/NIMH NIH HHS/ -- U54 GM094618/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 May 16;497(7449):338-43. doi: 10.1038/nature12167. Epub 2013 May 1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23636324" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Amino Acid Sequence ; Antineoplastic Agents/*chemistry/metabolism ; Binding Sites ; Crystallography, X-Ray ; Disulfides/chemistry ; Frizzled Receptors/chemistry/classification ; Humans ; Ligands ; Models, Molecular ; Molecular Sequence Data ; Phthalazines/*chemistry/metabolism ; Protein Structure, Tertiary ; Receptors, G-Protein-Coupled/*chemistry/classification/metabolism ; Structural Homology, Protein
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  • 57
    Publication Date: 2013-01-08
    Description: The initiation of gene transcription by RNA polymerase II is regulated by a plethora of proteins in human cells. The first general transcription factor to bind gene promoters is transcription factor IID (TFIID). TFIID triggers pre-initiation complex formation, functions as a coactivator by interacting with transcriptional activators and reads epigenetic marks. TFIID is a megadalton-sized multiprotein complex composed of TATA-box-binding protein (TBP) and 13 TBP-associated factors (TAFs). Despite its crucial role, the detailed architecture and assembly mechanism of TFIID remain elusive. Histone fold domains are prevalent in TAFs, and histone-like tetramer and octamer structures have been proposed in TFIID. A functional core-TFIID subcomplex was revealed in Drosophila nuclei, consisting of a subset of TAFs (TAF4, TAF5, TAF6, TAF9 and TAF12). These core subunits are thought to be present in two copies in holo-TFIID, in contrast to TBP and other TAFs that are present in a single copy, conveying a transition from symmetry to asymmetry in the TFIID assembly pathway. Here we present the structure of human core-TFIID determined by cryo-electron microscopy at 11.6 A resolution. Our structure reveals a two-fold symmetric, interlaced architecture, with pronounced protrusions, that accommodates all conserved structural features of the TAFs including the histone folds. We further demonstrate that binding of one TAF8-TAF10 complex breaks the original symmetry of core-TFIID. We propose that the resulting asymmetric structure serves as a functional scaffold to nucleate holo-TFIID assembly, by accreting one copy each of the remaining TAFs and TBP.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bieniossek, Christoph -- Papai, Gabor -- Schaffitzel, Christiane -- Garzoni, Frederic -- Chaillet, Maxime -- Scheer, Elisabeth -- Papadopoulos, Petros -- Tora, Laszlo -- Schultz, Patrick -- Berger, Imre -- England -- Nature. 2013 Jan 31;493(7434):699-702. doi: 10.1038/nature11791. Epub 2013 Jan 6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉European Molecular Biology Laboratory Grenoble Outstation, Unit of Virus Host Cell Interactions UVHCI, UJF-CNRS-EMBL Unite Mixte International UMI 3265, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9, France.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23292512" target="_blank"〉PubMed〈/a〉
    Keywords: Cells, Cultured ; Cryoelectron Microscopy ; HeLa Cells ; Humans ; *Models, Molecular ; Protein Binding ; Protein Structure, Tertiary ; Transcription Factor TFIID/*chemistry/genetics/metabolism
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  • 58
    Publication Date: 2013-10-29
    Description: Integrins have a critical role in thrombosis and haemostasis. Antagonists of the platelet integrin alphaIIbbeta3 are potent anti-thrombotic drugs, but also have the life-threatening adverse effect of causing bleeding. It is therefore desirable to develop new antagonists that do not cause bleeding. Integrins transmit signals bidirectionally. Inside-out signalling activates integrins through a talin-dependent mechanism. Integrin ligation mediates thrombus formation and outside-in signalling, which requires Galpha13 and greatly expands thrombi. Here we show that Galpha13 and talin bind to mutually exclusive but distinct sites within the integrin beta3 cytoplasmic domain in opposing waves. The first talin-binding wave mediates inside-out signalling and also ligand-induced integrin activation, but is not required for outside-in signalling. Integrin ligation induces transient talin dissociation and Galpha13 binding to an EXE motif (in which X denotes any residue), which selectively mediates outside-in signalling and platelet spreading. The second talin-binding wave is associated with clot retraction. An EXE-motif-based inhibitor of Galpha13-integrin interaction selectively abolishes outside-in signalling without affecting integrin ligation, and suppresses occlusive arterial thrombosis without affecting bleeding time. Thus, we have discovered a new mechanism for the directional switch of integrin signalling and, on the basis of this mechanism, designed a potent new anti-thrombotic drug that does not cause bleeding.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3823815/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3823815/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Shen, Bo -- Zhao, Xiaojuan -- O'Brien, Kelly A -- Stojanovic-Terpo, Aleksandra -- Delaney, M Keegan -- Kim, Kyungho -- Cho, Jaehyung -- Lam, Stephen C-T -- Du, Xiaoping -- HL062350/HL/NHLBI NIH HHS/ -- HL080264/HL/NHLBI NIH HHS/ -- HL109439/HL/NHLBI NIH HHS/ -- R01 HL080264/HL/NHLBI NIH HHS/ -- R01 HL109439/HL/NHLBI NIH HHS/ -- T32 HL007829/HL/NHLBI NIH HHS/ -- England -- Nature. 2013 Nov 7;503(7474):131-5. doi: 10.1038/nature12613. Epub 2013 Oct 27.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pharmacology, University of Illinois at Chicago, 835 South Wolcott Avenue, Chicago, Illinois 60612, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24162846" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Amino Acid Sequence ; Animals ; Antithrombins/adverse effects/*pharmacology/therapeutic use ; Binding Sites ; Bleeding Time ; *Cell Polarity ; Cytoplasm/metabolism ; GTP-Binding Protein alpha Subunits, G12-G13/metabolism ; Hemorrhage/chemically induced ; Humans ; Integrin beta3/chemistry/genetics/metabolism ; Integrins/chemistry/deficiency/genetics/*metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Molecular Sequence Data ; Platelet Glycoprotein GPIIb-IIIa Complex/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Signal Transduction/*drug effects ; Talin/metabolism ; Thrombosis/*drug therapy/metabolism/pathology
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  • 59
    Publication Date: 2013-12-18
    Description: Prokaryotic viruses have evolved various mechanisms to transport their genomes across bacterial cell walls. Many bacteriophages use a tail to perform this function, whereas tail-less phages rely on host organelles. However, the tail-less, icosahedral, single-stranded DNA PhiX174-like coliphages do not fall into these well-defined infection processes. For these phages, DNA delivery requires a DNA pilot protein. Here we show that the PhiX174 pilot protein H oligomerizes to form a tube whose function is most probably to deliver the DNA genome across the host's periplasmic space to the cytoplasm. The 2.4 A resolution crystal structure of the in vitro assembled H protein's central domain consists of a 170 A-long alpha-helical barrel. The tube is constructed of ten alpha-helices with their amino termini arrayed in a right-handed super-helical coiled-coil and their carboxy termini arrayed in a left-handed super-helical coiled-coil. Genetic and biochemical studies demonstrate that the tube is essential for infectivity but does not affect in vivo virus assembly. Cryo-electron tomograms show that tubes span the periplasmic space and are present while the genome is being delivered into the host cell's cytoplasm. Both ends of the H protein contain transmembrane domains, which anchor the assembled tubes into the inner and outer cell membranes. The central channel of the H-protein tube is lined with amide and guanidinium side chains. This may be a general property of viral DNA conduits and is likely to be critical for efficient genome translocation into the host.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sun, Lei -- Young, Lindsey N -- Zhang, Xinzheng -- Boudko, Sergei P -- Fokine, Andrei -- Zbornik, Erica -- Roznowski, Aaron P -- Molineux, Ian J -- Rossmann, Michael G -- Fane, Bentley A -- England -- Nature. 2014 Jan 16;505(7483):432-5. doi: 10.1038/nature12816. Epub 2013 Dec 15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA [2]. ; 1] School of Plant Sciences and the BIO5 Institute, University of Arizona, Tucson, Arizona 85721, USA [2]. ; 1] Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA [2] The Research Department, Shriner's Hospital for Children, Portland, Oregon 97239, USA. ; Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA. ; School of Plant Sciences and the BIO5 Institute, University of Arizona, Tucson, Arizona 85721, USA. ; Molecular Genetics and Microbiology, Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24336205" target="_blank"〉PubMed〈/a〉
    Keywords: Bacteriophage phi X 174/*chemistry/*metabolism/ultrastructure ; Biological Transport ; Cryoelectron Microscopy ; Crystallography, X-Ray ; Cytoplasm/metabolism/ultrastructure/virology ; DNA, Viral/*metabolism/ultrastructure ; Escherichia coli/cytology/ultrastructure/*virology ; Genome, Viral ; Models, Molecular ; Periplasm/metabolism/ultrastructure ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Viral Proteins/chemistry/metabolism/ultrastructure ; *Virus Assembly
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  • 60
    Publication Date: 2013-11-22
    Description: Despite recent advances in crystallography and the availability of G-protein-coupled receptor (GPCR) structures, little is known about the mechanism of their activation process, as only the beta2 adrenergic receptor (beta2AR) and rhodopsin have been crystallized in fully active conformations. Here we report the structure of an agonist-bound, active state of the human M2 muscarinic acetylcholine receptor stabilized by a G-protein mimetic camelid antibody fragment isolated by conformational selection using yeast surface display. In addition to the expected changes in the intracellular surface, the structure reveals larger conformational changes in the extracellular region and orthosteric binding site than observed in the active states of the beta2AR and rhodopsin. We also report the structure of the M2 receptor simultaneously bound to the orthosteric agonist iperoxo and the positive allosteric modulator LY2119620. This structure reveals that LY2119620 recognizes a largely pre-formed binding site in the extracellular vestibule of the iperoxo-bound receptor, inducing a slight contraction of this outer binding pocket. These structures offer important insights into the activation mechanism and allosteric modulation of muscarinic receptors.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4020789/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4020789/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kruse, Andrew C -- Ring, Aaron M -- Manglik, Aashish -- Hu, Jianxin -- Hu, Kelly -- Eitel, Katrin -- Hubner, Harald -- Pardon, Els -- Valant, Celine -- Sexton, Patrick M -- Christopoulos, Arthur -- Felder, Christian C -- Gmeiner, Peter -- Steyaert, Jan -- Weis, William I -- Garcia, K Christopher -- Wess, Jurgen -- Kobilka, Brian K -- GM08311806/GM/NIGMS NIH HHS/ -- NS02847123/NS/NINDS NIH HHS/ -- T32 GM008294/GM/NIGMS NIH HHS/ -- U19 GM106990/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- Intramural NIH HHS/ -- England -- Nature. 2013 Dec 5;504(7478):101-6. doi: 10.1038/nature12735. Epub 2013 Nov 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 279 Campus Drive, Stanford, California 94305, USA [2].〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24256733" target="_blank"〉PubMed〈/a〉
    Keywords: Allosteric Regulation ; Binding Sites ; Cytoplasm/metabolism ; Humans ; Isoxazoles/chemistry/metabolism ; *Models, Molecular ; Protein Binding ; Protein Structure, Tertiary ; Quaternary Ammonium Compounds/chemistry/metabolism ; Receptors, Muscarinic/*chemistry/*metabolism
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  • 61
    Publication Date: 2013-08-27
    Description: The KCNH voltage-dependent potassium channels (ether-a-go-go, EAG; EAG-related gene, ERG; EAG-like channels, ELK) are important regulators of cellular excitability and have key roles in diseases such as cardiac long QT syndrome type 2 (LQT2), epilepsy, schizophrenia and cancer. The intracellular domains of KCNH channels are structurally distinct from other voltage-gated channels. The amino-terminal region contains an eag domain, which is composed of a Per-Arnt-Sim (PAS) domain and a PAS-cap domain, whereas the carboxy-terminal region contains a cyclic nucleotide-binding homology domain (CNBHD), which is connected to the pore through a C-linker domain. Many disease-causing mutations localize to these specialized intracellular domains, which underlie the unique gating and regulation of KCNH channels. It has been suggested that the eag domain may regulate the channel by interacting with either the S4-S5 linker or the CNBHD. Here we present a 2 A resolution crystal structure of the eag domain-CNBHD complex of the mouse EAG1 (also known as KCNH1) channel. It displays extensive interactions between the eag domain and the CNBHD, indicating that the regulatory mechanism of the eag domain primarily involves the CNBHD. Notably, the structure reveals that a number of LQT2 mutations at homologous positions in human ERG, in addition to cancer-associated mutations in EAG channels, localize to the eag domain-CNBHD interface. Furthermore, mutations at the interface produced marked effects on channel gating, demonstrating the important physiological role of the eag domain-CNBHD interaction. Our structure of the eag domain-CNBHD complex of mouse EAG1 provides unique insights into the physiological and pathophysiological mechanisms of KCNH channels.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3910112/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3910112/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Haitin, Yoni -- Carlson, Anne E -- Zagotta, William N -- F32 HL095241/HL/NHLBI NIH HHS/ -- R01 EY010329/EY/NEI NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2013 Sep 19;501(7467):444-8. doi: 10.1038/nature12487. Epub 2013 Aug 25.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology and Biophysics, University of Washington School of Medicine, Seattle, Washington 98195, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23975098" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Binding Sites ; Crystallography, X-Ray ; Ether-A-Go-Go Potassium Channels/*chemistry/genetics/*metabolism ; Humans ; Mice ; Models, Molecular ; Nucleotides, Cyclic/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Static Electricity
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  • 62
    Publication Date: 2013-10-08
    Description: Magnetotactic bacteria align along the Earth's magnetic field using an organelle called the magnetosome, a biomineralized magnetite (Fe(II)Fe(III)2O4) or greigite (Fe(II)Fe(III)2S4) crystal embedded in a lipid vesicle. Although the need for both iron(II) and iron(III) is clear, little is known about the biological mechanisms controlling their ratio. Here we present the structure of the magnetosome-associated protein MamP and find that it is built on a unique arrangement of a self-plugged PDZ domain fused to two magnetochrome domains, defining a new class of c-type cytochrome exclusively found in magnetotactic bacteria. Mutational analysis, enzyme kinetics, co-crystallization with iron(II) and an in vitro MamP-assisted magnetite production assay establish MamP as an iron oxidase that contributes to the formation of iron(III) ferrihydrite eventually required for magnetite crystal growth in vivo. These results demonstrate the molecular mechanisms of iron management taking place inside the magnetosome and highlight the role of magnetochrome in iron biomineralization.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Siponen, Marina I -- Legrand, Pierre -- Widdrat, Marc -- Jones, Stephanie R -- Zhang, Wei-Jia -- Chang, Michelle C Y -- Faivre, Damien -- Arnoux, Pascal -- Pignol, David -- T32 GM066698/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Oct 31;502(7473):681-4. doi: 10.1038/nature12573. Epub 2013 Oct 6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Commissariat a l'Energie Atomique et aux Energies Alternatives, Direction des Sciences du Vivant, Institut de Biologie Environnementale et de Biotechnologies,, F-13108, France [2] Centre National de la Recherche Scientifique, Unite Mixte de Recherche Biologie Vegetale et Microbiologie Environnementales, Saint-Paul-lez-Durance, F-13108, France [3] Aix-Marseille Universite, Saint-Paul-lez-Durance, F-13108, France.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24097349" target="_blank"〉PubMed〈/a〉
    Keywords: Bacteria/*cytology/enzymology/genetics/*metabolism ; Bacterial Proteins/chemistry/genetics/metabolism ; Conserved Sequence ; Ferric Compounds/metabolism ; Ferrosoferric Oxide/*metabolism ; Genes, Bacterial/genetics ; Iron/metabolism ; Magnetosomes/*metabolism ; Models, Molecular ; Oxidation-Reduction ; Oxidoreductases/chemistry/genetics/metabolism ; Protein Multimerization ; Protein Structure, Tertiary ; Static Electricity
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  • 63
    Publication Date: 2013-07-19
    Description: Binding of the glucagon peptide to the glucagon receptor (GCGR) triggers the release of glucose from the liver during fasting; thus GCGR plays an important role in glucose homeostasis. Here we report the crystal structure of the seven transmembrane helical domain of human GCGR at 3.4 A resolution, complemented by extensive site-specific mutagenesis, and a hybrid model of glucagon bound to GCGR to understand the molecular recognition of the receptor for its native ligand. Beyond the shared seven transmembrane fold, the GCGR transmembrane domain deviates from class A G-protein-coupled receptors with a large ligand-binding pocket and the first transmembrane helix having a 'stalk' region that extends three alpha-helical turns above the plane of the membrane. The stalk positions the extracellular domain (~12 kilodaltons) relative to the membrane to form the glucagon-binding site that captures the peptide and facilitates the insertion of glucagon's amino terminus into the seven transmembrane domain.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3820480/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3820480/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Siu, Fai Yiu -- He, Min -- de Graaf, Chris -- Han, Gye Won -- Yang, Dehua -- Zhang, Zhiyun -- Zhou, Caihong -- Xu, Qingping -- Wacker, Daniel -- Joseph, Jeremiah S -- Liu, Wei -- Lau, Jesper -- Cherezov, Vadim -- Katritch, Vsevolod -- Wang, Ming-Wei -- Stevens, Raymond C -- F32 DK088392/DK/NIDDK NIH HHS/ -- P50 GM073197/GM/NIGMS NIH HHS/ -- P50GM073197/GM/NIGMS NIH HHS/ -- U54 GM094586/GM/NIGMS NIH HHS/ -- U54 GM094618/GM/NIGMS NIH HHS/ -- Y1-CO-1020/CO/NCI NIH HHS/ -- Y1-GM-1104/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Jul 25;499(7459):444-9. doi: 10.1038/nature12393. Epub 2013 Jul 17.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23863937" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Binding Sites ; Cell Membrane/metabolism ; Crystallography, X-Ray ; Glucagon/chemistry/metabolism ; Humans ; Ligands ; Models, Molecular ; Molecular Sequence Data ; Mutagenesis, Site-Directed ; Protein Binding ; Protein Structure, Tertiary ; Receptors, CXCR4/chemistry/classification ; Receptors, Glucagon/*chemistry/*classification/genetics/metabolism
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  • 64
    Publication Date: 2013-10-29
    Description: Members of the CD36 superfamily of scavenger receptor proteins are important regulators of lipid metabolism and innate immunity. They recognize normal and modified lipoproteins, as well as pathogen-associated molecular patterns. The family consists of three members: SR-BI (which delivers cholesterol to the liver and steroidogenic organs and is a co-receptor for hepatitis C virus), LIMP-2/LGP85 (which mediates lysosomal delivery of beta-glucocerebrosidase and serves as a receptor for enterovirus 71 and coxsackieviruses) and CD36 (a fatty-acid transporter and receptor for phagocytosis of effete cells and Plasmodium-infected erythrocytes). Notably, CD36 is also a receptor for modified lipoproteins and beta-amyloid, and has been implicated in the pathogenesis of atherosclerosis and of Alzheimer's disease. Despite their prominent roles in health and disease, understanding the function and abnormalities of the CD36 family members has been hampered by the paucity of information about their structure. Here we determine the crystal structure of LIMP-2 and infer, by homology modelling, the structure of SR-BI and CD36. LIMP-2 shows a helical bundle where beta-glucocerebrosidase binds, and where ligands are most likely to bind to SR-BI and CD36. Remarkably, the crystal structure also shows the existence of a large cavity that traverses the entire length of the molecule. Mutagenesis of SR-BI indicates that the cavity serves as a tunnel through which cholesterol(esters) are delivered from the bound lipoprotein to the outer leaflet of the plasma membrane. We provide evidence supporting a model whereby lipidic constituents of the ligands attached to the receptor surface are handed off to the membrane through the tunnel, accounting for the selective lipid transfer characteristic of SR-BI and CD36.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Neculai, Dante -- Schwake, Michael -- Ravichandran, Mani -- Zunke, Friederike -- Collins, Richard F -- Peters, Judith -- Neculai, Mirela -- Plumb, Jonathan -- Loppnau, Peter -- Pizarro, Juan Carlos -- Seitova, Alma -- Trimble, William S -- Saftig, Paul -- Grinstein, Sergio -- Dhe-Paganon, Sirano -- MOP-102474/Canadian Institutes of Health Research/Canada -- MOP-126069/Canadian Institutes of Health Research/Canada -- Wellcome Trust/United Kingdom -- England -- Nature. 2013 Dec 5;504(7478):172-6. doi: 10.1038/nature12684. Epub 2013 Oct 27.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Cell Biology Program, The Hospital for Sick Children, Toronto M5G 1X8, Canada.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24162852" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Antigens, CD36/*metabolism ; CHO Cells ; Cricetulus ; HeLa Cells ; Humans ; Lysosome-Associated Membrane Glycoproteins/*chemistry/metabolism ; *Models, Molecular ; Protein Binding ; Protein Structure, Tertiary
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  • 65
    Publication Date: 2013-06-21
    Description: Allostery is an intrinsic property of many globular proteins and enzymes that is indispensable for cellular regulatory and feedback mechanisms. Recent theoretical and empirical observations indicate that allostery is also manifest in intrinsically disordered proteins, which account for a substantial proportion of the proteome. Many intrinsically disordered proteins are promiscuous binders that interact with multiple partners and frequently function as molecular hubs in protein interaction networks. The adenovirus early region 1A (E1A) oncoprotein is a prime example of a molecular hub intrinsically disordered protein. E1A can induce marked epigenetic reprogramming of the cell within hours after infection, through interactions with a diverse set of partners that include key host regulators such as the general transcriptional coactivator CREB binding protein (CBP), its paralogue p300, and the retinoblastoma protein (pRb; also called RB1). Little is known about the allosteric effects at play in E1A-CBP-pRb interactions, or more generally in hub intrinsically disordered protein interaction networks. Here we used single-molecule fluorescence resonance energy transfer (smFRET) to study coupled binding and folding processes in the ternary E1A system. The low concentrations used in these high-sensitivity experiments proved to be essential for these studies, which are challenging owing to a combination of E1A aggregation propensity and high-affinity binding interactions. Our data revealed that E1A-CBP-pRb interactions have either positive or negative cooperativity, depending on the available E1A interaction sites. This striking cooperativity switch enables fine-tuning of the thermodynamic accessibility of the ternary versus binary E1A complexes, and may permit a context-specific tuning of associated downstream signalling outputs. Such a modulation of allosteric interactions is probably a common mechanism in molecular hub intrinsically disordered protein function.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3718496/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3718496/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ferreon, Allan Chris M -- Ferreon, Josephine C -- Wright, Peter E -- Deniz, Ashok A -- CA96865/CA/NCI NIH HHS/ -- GM066833/GM/NIGMS NIH HHS/ -- R01 CA096865/CA/NCI NIH HHS/ -- R01 GM066833/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Jun 20;498(7454):390-4. doi: 10.1038/nature12294.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23783631" target="_blank"〉PubMed〈/a〉
    Keywords: Adenovirus E1A Proteins/*chemistry/*metabolism ; *Allosteric Regulation ; Amino Acid Motifs ; Animals ; Anisotropy ; CREB-Binding Protein/chemistry/metabolism ; Fluorescence Resonance Energy Transfer ; Humans ; Mice ; Models, Molecular ; Protein Binding ; Protein Folding ; Protein Structure, Tertiary ; Retinoblastoma Protein/chemistry/metabolism ; Thermodynamics ; p300-CBP Transcription Factors/chemistry
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  • 66
    Publication Date: 2013-06-25
    Description: Glutamate transporters are integral membrane proteins that catalyse neurotransmitter uptake from the synaptic cleft into the cytoplasm of glial cells and neurons. Their mechanism of action involves transitions between extracellular (outward)-facing and intracellular (inward)-facing conformations, whereby substrate binding sites become accessible to either side of the membrane. This process has been proposed to entail transmembrane movements of three discrete transport domains within a trimeric scaffold. Using single-molecule fluorescence resonance energy transfer (smFRET) imaging, we have directly observed large-scale transport domain movements in a bacterial homologue of glutamate transporters. We find that individual transport domains alternate between periods of quiescence and periods of rapid transitions, reminiscent of bursting patterns first recorded in single ion channels using patch-clamp methods. We propose that the switch to the dynamic mode in glutamate transporters is due to separation of the transport domain from the trimeric scaffold, which precedes domain movements across the bilayer. This spontaneous dislodging of the substrate-loaded transport domain is approximately 100-fold slower than subsequent transmembrane movements and may be rate determining in the transport cycle.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3829612/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3829612/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Akyuz, Nurunisa -- Altman, Roger B -- Blanchard, Scott C -- Boudker, Olga -- 5U54GM087519/GM/NIGMS NIH HHS/ -- R01 NS064357/NS/NINDS NIH HHS/ -- R01NS064357/NS/NINDS NIH HHS/ -- U54 GM087519/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Oct 3;502(7469):114-8. doi: 10.1038/nature12265. Epub 2013 Jun 23.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology and Biophysics, Weill Cornell Medical College, 1300 York Avenue, New York, New York 10064, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23792560" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Transport System X-AG/*chemistry/genetics/*metabolism ; Aspartic Acid/chemistry ; Biological Transport ; Fluorescence Resonance Energy Transfer ; *Models, Molecular ; Mutation ; Protein Binding ; Protein Structure, Tertiary ; Pyrococcus horikoshii/chemistry/genetics/*metabolism ; Sodium/chemistry
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  • 67
    Publication Date: 2013-03-15
    Description: A hallmark of histone H3 lysine 9 (H3K9)-methylated heterochromatin, conserved from the fission yeast Schizosaccharomyces pombe to humans, is its ability to spread to adjacent genomic regions. Central to heterochromatin spread is heterochromatin protein 1 (HP1), which recognizes H3K9-methylated chromatin, oligomerizes and forms a versatile platform that participates in diverse nuclear functions, ranging from gene silencing to chromosome segregation. How HP1 proteins assemble on methylated nucleosomal templates and how the HP1-nucleosome complex achieves functional versatility remain poorly understood. Here we show that binding of the key S. pombe HP1 protein, Swi6, to methylated nucleosomes drives a switch from an auto-inhibited state to a spreading-competent state. In the auto-inhibited state, a histone-mimic sequence in one Swi6 monomer blocks methyl-mark recognition by the chromodomain of another monomer. Auto-inhibition is relieved by recognition of two template features, the H3K9 methyl mark and nucleosomal DNA. Cryo-electron-microscopy-based reconstruction of the Swi6-nucleosome complex provides the overall architecture of the spreading-competent state in which two unbound chromodomain sticky ends appear exposed. Disruption of the switch between the auto-inhibited and spreading-competent states disrupts heterochromatin assembly and gene silencing in vivo. These findings are reminiscent of other conditionally activated polymerization processes, such as actin nucleation, and open up a new class of regulatory mechanisms that operate on chromatin in vivo.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3907283/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3907283/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Canzio, Daniele -- Liao, Maofu -- Naber, Nariman -- Pate, Edward -- Larson, Adam -- Wu, Shenping -- Marina, Diana B -- Garcia, Jennifer F -- Madhani, Hiten D -- Cooke, Roger -- Schuck, Peter -- Cheng, Yifan -- Narlikar, Geeta J -- AR053720/AR/NIAMS NIH HHS/ -- R01 AR062279/AR/NIAMS NIH HHS/ -- R01 GM071801/GM/NIGMS NIH HHS/ -- R01GM071801/GM/NIGMS NIH HHS/ -- Intramural NIH HHS/ -- England -- Nature. 2013 Apr 18;496(7445):377-81. doi: 10.1038/nature12032. Epub 2013 Mar 13.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry and Biophysics, University of California San Francisco, California 94158, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23485968" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; *Chromatin Assembly and Disassembly ; Chromosomal Proteins, Non-Histone/*antagonists & ; inhibitors/*chemistry/*metabolism/ultrastructure ; Cryoelectron Microscopy ; Gene Silencing ; Heterochromatin/chemistry/*metabolism/ultrastructure ; Histones/chemistry/metabolism ; Methylation ; Models, Molecular ; Molecular Sequence Data ; Nucleosomes/chemistry/genetics/metabolism/ultrastructure ; Protein Structure, Tertiary ; Schizosaccharomyces/genetics/*metabolism ; Schizosaccharomyces pombe Proteins/antagonists & ; inhibitors/*chemistry/*metabolism/ultrastructure ; Xenopus laevis
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  • 68
    Publication Date: 2013-04-05
    Description: Current human immunodeficiency virus-1 (HIV-1) vaccines elicit strain-specific neutralizing antibodies. However, cross-reactive neutralizing antibodies arise in approximately 20% of HIV-1-infected individuals, and details of their generation could provide a blueprint for effective vaccination. Here we report the isolation, evolution and structure of a broadly neutralizing antibody from an African donor followed from the time of infection. The mature antibody, CH103, neutralized approximately 55% of HIV-1 isolates, and its co-crystal structure with the HIV-1 envelope protein gp120 revealed a new loop-based mechanism of CD4-binding-site recognition. Virus and antibody gene sequencing revealed concomitant virus evolution and antibody maturation. Notably, the unmutated common ancestor of the CH103 lineage avidly bound the transmitted/founder HIV-1 envelope glycoprotein, and evolution of antibody neutralization breadth was preceded by extensive viral diversification in and near the CH103 epitope. These data determine the viral and antibody evolution leading to induction of a lineage of HIV-1 broadly neutralizing antibodies, and provide insights into strategies to elicit similar antibodies by vaccination.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3637846/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3637846/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Liao, Hua-Xin -- Lynch, Rebecca -- Zhou, Tongqing -- Gao, Feng -- Alam, S Munir -- Boyd, Scott D -- Fire, Andrew Z -- Roskin, Krishna M -- Schramm, Chaim A -- Zhang, Zhenhai -- Zhu, Jiang -- Shapiro, Lawrence -- NISC Comparative Sequencing Program -- Mullikin, James C -- Gnanakaran, S -- Hraber, Peter -- Wiehe, Kevin -- Kelsoe, Garnett -- Yang, Guang -- Xia, Shi-Mao -- Montefiori, David C -- Parks, Robert -- Lloyd, Krissey E -- Scearce, Richard M -- Soderberg, Kelly A -- Cohen, Myron -- Kamanga, Gift -- Louder, Mark K -- Tran, Lillian M -- Chen, Yue -- Cai, Fangping -- Chen, Sheri -- Moquin, Stephanie -- Du, Xiulian -- Joyce, M Gordon -- Srivatsan, Sanjay -- Zhang, Baoshan -- Zheng, Anqi -- Shaw, George M -- Hahn, Beatrice H -- Kepler, Thomas B -- Korber, Bette T M -- Kwong, Peter D -- Mascola, John R -- Haynes, Barton F -- AI067854/AI/NIAID NIH HHS/ -- AI100645/AI/NIAID NIH HHS/ -- P30 AI050410/AI/NIAID NIH HHS/ -- UM1 AI100645/AI/NIAID NIH HHS/ -- Intramural NIH HHS/ -- England -- Nature. 2013 Apr 25;496(7446):469-76. doi: 10.1038/nature12053. Epub 2013 Apr 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Duke University Human Vaccine Institute, Departments of Medicine and Immunology, Duke University School of Medicine, Durham, North Carolina 27710, USA. hliao@duke.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23552890" target="_blank"〉PubMed〈/a〉
    Keywords: AIDS Vaccines/immunology ; Africa ; Amino Acid Sequence ; Antibodies, Monoclonal/chemistry/genetics/immunology ; Antibodies, Neutralizing/*chemistry/genetics/*immunology ; Antigens, CD4/chemistry/immunology ; Cell Lineage ; Cells, Cultured ; Clone Cells/cytology ; Cross Reactions/immunology ; Crystallography, X-Ray ; Epitopes/chemistry/immunology ; *Evolution, Molecular ; HIV Antibodies/*chemistry/genetics/*immunology ; HIV Envelope Protein gp120/chemistry/genetics/immunology/metabolism ; HIV-1/*chemistry/classification/*immunology ; Humans ; Models, Molecular ; Molecular Sequence Data ; Mutation ; Neutralization Tests ; Phylogeny ; Protein Structure, Tertiary
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  • 69
    Publication Date: 2013-03-29
    Description: Electron transfer reactions are essential for life because they underpin oxidative phosphorylation and photosynthesis, processes leading to the generation of ATP, and are involved in many reactions of intermediary metabolism. Key to these roles is the formation of transient inter-protein electron transfer complexes. The structural basis for the control of specificity between partner proteins is lacking because these weak transient complexes have remained largely intractable for crystallographic studies. Inter-protein electron transfer processes are central to all of the key steps of denitrification, an alternative form of respiration in which bacteria reduce nitrate or nitrite to N2 through the gaseous intermediates nitric oxide (NO) and nitrous oxide (N2O) when oxygen concentrations are limiting. The one-electron reduction of nitrite to NO, a precursor to N2O, is performed by either a haem- or copper-containing nitrite reductase (CuNiR) where they receive an electron from redox partner proteins a cupredoxin or a c-type cytochrome. Here we report the structures of the newly characterized three-domain haem-c-Cu nitrite reductase from Ralstonia pickettii (RpNiR) at 1.01 A resolution and its M92A and P93A mutants. Very high resolution provides the first view of the atomic detail of the interface between the core trimeric cupredoxin structure of CuNiR and the tethered cytochrome c domain that allows the enzyme to function as an effective self-electron transfer system where the donor and acceptor proteins are fused together by genomic acquisition for functional advantage. Comparison of RpNiR with the binary complex of a CuNiR with a donor protein, AxNiR-cytc551 (ref. 6), and mutagenesis studies provide direct evidence for the importance of a hydrogen-bonded water at the interface in electron transfer. The structure also provides an explanation for the preferential binding of nitrite to the reduced copper ion at the active site in RpNiR, in contrast to other CuNiRs where reductive inactivation occurs, preventing substrate binding.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3672994/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3672994/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Antonyuk, Svetlana V -- Han, Cong -- Eady, Robert R -- Hasnain, S Samar -- 097826/Z/11/Z/Wellcome Trust/United Kingdom -- BB/G005869/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- England -- Nature. 2013 Apr 4;496(7443):123-6. doi: 10.1038/nature11996. Epub 2013 Mar 27.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZX, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23535590" target="_blank"〉PubMed〈/a〉
    Keywords: Azurin/chemistry/metabolism ; Catalytic Domain ; Copper/chemistry/metabolism ; Cytochromes c/chemistry/metabolism ; *Electron Transport ; Hydrogen Bonding ; Models, Molecular ; Mutant Proteins/chemistry/genetics/metabolism ; Nitrite Reductases/*chemistry/genetics/*metabolism ; Nitrites/chemistry/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Protons ; Ralstonia pickettii/*enzymology ; Water/chemistry/metabolism
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  • 70
    Publication Date: 2013-09-13
    Description: Successful infection by enteric bacterial pathogens depends on the ability of the bacteria to colonize the gut, replicate in host tissues and disseminate to other hosts. Pathogens such as Salmonella, Shigella and enteropathogenic and enterohaemorrhagic (EPEC and EHEC, respectively) Escherichia coli use a type III secretion system (T3SS) to deliver virulence effector proteins into host cells during infection that promote colonization and interfere with antimicrobial host responses. Here we report that the T3SS effector NleB1 from EPEC binds to host cell death-domain-containing proteins and thereby inhibits death receptor signalling. Protein interaction studies identified FADD, TRADD and RIPK1 as binding partners of NleB1. NleB1 expressed ectopically or injected by the bacterial T3SS prevented Fas ligand or TNF-induced formation of the canonical death-inducing signalling complex (DISC) and proteolytic activation of caspase-8, an essential step in death-receptor-induced apoptosis. This inhibition depended on the N-acetylglucosamine transferase activity of NleB1, which specifically modified Arg 117 in the death domain of FADD. The importance of the death receptor apoptotic pathway to host defence was demonstrated using mice deficient in the FAS signalling pathway, which showed delayed clearance of the EPEC-like mouse pathogen Citrobacter rodentium and reversion to virulence of an nleB mutant. The activity of NleB suggests that EPEC and other attaching and effacing pathogens antagonize death-receptor-induced apoptosis of infected cells, thereby blocking a major antimicrobial host response.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3836246/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3836246/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Pearson, Jaclyn S -- Giogha, Cristina -- Ong, Sze Ying -- Kennedy, Catherine L -- Kelly, Michelle -- Robinson, Keith S -- Lung, Tania Wong Fok -- Mansell, Ashley -- Riedmaier, Patrice -- Oates, Clare V L -- Zaid, Ali -- Muhlen, Sabrina -- Crepin, Valerie F -- Marches, Olivier -- Ang, Ching-Seng -- Williamson, Nicholas A -- O'Reilly, Lorraine A -- Bankovacki, Aleksandra -- Nachbur, Ueli -- Infusini, Giuseppe -- Webb, Andrew I -- Silke, John -- Strasser, Andreas -- Frankel, Gad -- Hartland, Elizabeth L -- 090325/Wellcome Trust/United Kingdom -- Wellcome Trust/United Kingdom -- England -- Nature. 2013 Sep 12;501(7466):247-51. doi: 10.1038/nature12524.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Microbiology and Immunology, University of Melbourne, Victoria 3010, Australia.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24025841" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Antigens, CD95/deficiency/metabolism ; Caspase 8/metabolism ; Cell Death ; Citrobacter rodentium/pathogenicity/physiology ; Enteropathogenic Escherichia coli/*metabolism/pathogenicity ; Enzyme Activation ; Escherichia coli Infections/*metabolism/*microbiology/pathology ; Escherichia coli Proteins/*metabolism ; Fas Ligand Protein/antagonists & inhibitors/metabolism ; Fas-Associated Death Domain Protein/chemistry/metabolism ; Female ; Gastrointestinal Tract/*microbiology ; HEK293 Cells ; HeLa Cells ; Humans ; Male ; Mice ; N-Acetylglucosaminyltransferases/metabolism ; Protein Structure, Tertiary ; Receptor-Interacting Protein Serine-Threonine Kinases/chemistry/metabolism ; *Signal Transduction ; TNF Receptor-Associated Death Domain Protein/chemistry/metabolism ; Virulence Factors/*metabolism
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  • 71
    Publication Date: 2013-12-03
    Description: CAAX proteins have essential roles in multiple signalling pathways, controlling processes such as proliferation, differentiation and carcinogenesis. The approximately 120 mammalian CAAX proteins function at cellular membranes and include the Ras superfamily of small GTPases, nuclear lamins, the gamma-subunit of heterotrimeric GTPases, and several protein kinases and phosphatases. The proper localization of CAAX proteins to cell membranes is orchestrated by a series of post-translational modifications of the carboxy-terminal CAAX motifs (where C is cysteine, A is an aliphatic amino acid and X is any amino acid). These reactions involve prenylation of the cysteine residue, cleavage at the AAX tripeptide and methylation of the carboxyl-prenylated cysteine residue. The major CAAX protease activity is mediated by Rce1 (Ras and a-factor converting enzyme 1), an intramembrane protease (IMP) of the endoplasmic reticulum. Information on the architecture and proteolytic mechanism of Rce1 has been lacking. Here we report the crystal structure of a Methanococcus maripaludis homologue of Rce1, whose endopeptidase specificity for farnesylated peptides mimics that of eukaryotic Rce1. Its structure, comprising eight transmembrane alpha-helices, and catalytic site are distinct from those of other IMPs. The catalytic residues are located approximately 10 A into the membrane and are exposed to the cytoplasm and membrane through a conical cavity that accommodates the prenylated CAAX substrate. We propose that the farnesyl lipid binds to a site at the opening of two transmembrane alpha-helices, which results in the scissile bond being positioned adjacent to a glutamate-activated nucleophilic water molecule. This study suggests that Rce1 is the founding member of a novel IMP family, the glutamate IMPs.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3864837/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3864837/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Manolaridis, Ioannis -- Kulkarni, Kiran -- Dodd, Roger B -- Ogasawara, Satoshi -- Zhang, Ziguo -- Bineva, Ganka -- O'Reilly, Nicola -- Hanrahan, Sarah J -- Thompson, Andrew J -- Cronin, Nora -- Iwata, So -- Barford, David -- 100140/Wellcome Trust/United Kingdom -- A2560/Cancer Research UK/United Kingdom -- A7403/Cancer Research UK/United Kingdom -- A8022/Cancer Research UK/United Kingdom -- BB/G023425/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- Cancer Research UK/United Kingdom -- England -- Nature. 2013 Dec 12;504(7479):301-5. doi: 10.1038/nature12754. Epub 2013 Dec 1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK [2]. ; 1] Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK [2] [3] Division of Biological Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India (K.K.); Cambridge Institute for Medical Research, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0XY, UK (R.B.D.). ; 1] Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK [2] Division of Biological Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India (K.K.); Cambridge Institute for Medical Research, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0XY, UK (R.B.D.). ; 1] Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan [2] JST, Research Acceleration Program, Membrane Protein Crystallography Project, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan. ; Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK. ; Cancer Research UK London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK. ; 1] Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan [2] JST, Research Acceleration Program, Membrane Protein Crystallography Project, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan [3] Department of Life Sciences, Imperial College, London SW7 2AZ, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24291792" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Amino Acid Sequence ; Animals ; Archaeal Proteins/chemistry/metabolism ; *Biocatalysis ; Conserved Sequence ; Crystallography, X-Ray ; Cysteine/metabolism ; DNA-Binding Proteins/chemistry/metabolism ; Endopeptidases/chemistry/metabolism ; Endoplasmic Reticulum/enzymology ; Escherichia coli Proteins/chemistry/metabolism ; Glutamic Acid/metabolism ; Humans ; Membrane Proteins/*chemistry/metabolism ; Metalloendopeptidases/chemistry/metabolism ; Methanococcus/*enzymology ; Mice ; Models, Molecular ; Molecular Sequence Data ; Peptide Hydrolases/*chemistry/classification/*metabolism ; *Prenylation ; Protein Structure, Tertiary ; Proto-Oncogene Proteins p21(ras)/chemistry/*metabolism ; Signal Transduction ; Substrate Specificity
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  • 72
    Publication Date: 2013-02-08
    Description: Mammalian telomeres repress DNA-damage activation at natural chromosome ends by recruiting specific inhibitors of the DNA-damage machinery that form a protective complex termed shelterin. Within this complex, TRF2 (also known as TERF2) has a crucial role in end protection through the suppression of ATM activation and the formation of end-to-end chromosome fusions. Here we address the molecular properties of TRF2 that are both necessary and sufficient to protect chromosome ends in mouse embryonic fibroblasts. Our data support a two-step mechanism for TRF2-mediated end protection. First, the dimerization domain of TRF2 is required to inhibit ATM activation, the key initial step involved in the activation of a DNA-damage response (DDR). Next, TRF2 independently suppresses the propagation of DNA-damage signalling downstream of ATM activation. This novel modulation of the DDR at telomeres occurs at the level of the E3 ubiquitin ligase RNF168 (ref. 3). Inhibition of RNF168 at telomeres involves the deubiquitinating enzyme BRCC3 and the ubiquitin ligase UBR5, and is sufficient to suppress chromosome end-to-end fusions. This two-step mechanism for TRF2-mediated end protection helps to explain the apparent paradox of frequent localization of DDR proteins at functional telomeres without concurrent induction of detrimental DNA-repair activities.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3733551/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3733551/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Okamoto, Keiji -- Bartocci, Cristina -- Ouzounov, Iliana -- Diedrich, Jolene K -- Yates, John R 3rd -- Denchi, Eros Lazzerini -- 5P41RR011823-17/RR/NCRR NIH HHS/ -- 8 P41 GM103533-17/GM/NIGMS NIH HHS/ -- AG038677/AG/NIA NIH HHS/ -- P41 GM103533/GM/NIGMS NIH HHS/ -- P41 RR011823/RR/NCRR NIH HHS/ -- R01 AG038677/AG/NIA NIH HHS/ -- England -- Nature. 2013 Feb 28;494(7438):502-5. doi: 10.1038/nature11873. Epub 2013 Feb 6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Chromosome Biology and Genomic Stability, Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23389450" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Ataxia Telangiectasia Mutated Proteins ; Cell Cycle Proteins/antagonists & inhibitors/metabolism ; Chromosomal Proteins, Non-Histone/metabolism ; Chromosomes, Mammalian/genetics/metabolism ; DNA Damage ; DNA Repair ; DNA-Binding Proteins/antagonists & inhibitors/metabolism ; Endopeptidases/deficiency/metabolism ; Enzyme Activation ; Mice ; Protein Multimerization ; Protein Structure, Tertiary ; Protein Transport ; Protein-Serine-Threonine Kinases/antagonists & inhibitors/metabolism ; Signal Transduction ; Telomere/genetics/metabolism ; Telomeric Repeat Binding Protein 2/chemistry/*metabolism ; Tumor Suppressor Proteins/antagonists & inhibitors/metabolism ; Ubiquitin-Protein Ligases/antagonists & inhibitors/metabolism
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  • 73
    Publication Date: 2013-04-16
    Description: The energy-coupling factor (ECF) transporters constitute a novel family of conserved membrane transporters in prokaryotes that have a similar domain organization to the ATP-binding cassette transporters. Each ECF transporter comprises a pair of cytosolic ATPases (the A and A' components, or EcfA and EcfA'), a membrane-embedded substrate-binding protein (the S component, or EcfS) and a transmembrane energy-coupling component (the T component, or EcfT) that links the EcfA-EcfA' subcomplex to EcfS. The structure and transport mechanism of the quaternary ECF transporter remain largely unknown. Here we report the crystal structure of a nucleotide-free ECF transporter from Lactobacillus brevis at a resolution of 3.5 A. The T component has a horseshoe-shaped open architecture, with five alpha-helices as transmembrane segments and two cytoplasmic alpha-helices as coupling modules connecting to the A and A' components. Strikingly, the S component, thought to be specific for hydroxymethyl pyrimidine, lies horizontally along the lipid membrane and is bound exclusively by the five transmembrane segments and the two cytoplasmic helices of the T component. These structural features suggest a plausible working model for the transport cycle of the ECF transporters.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wang, Tingliang -- Fu, Guobin -- Pan, Xiaojing -- Wu, Jianping -- Gong, Xinqi -- Wang, Jiawei -- Shi, Yigong -- England -- Nature. 2013 May 9;497(7448):272-6. doi: 10.1038/nature12045. Epub 2013 Apr 14.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Ministry of Education Key Laboratory of Protein Science, Tsinghua University, Beijing 100084, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23584587" target="_blank"〉PubMed〈/a〉
    Keywords: ATP-Binding Cassette Transporters/chemistry ; Anti-Bacterial Agents ; Bacterial Proteins/*chemistry/metabolism ; Crystallography, X-Ray ; Cytoplasm/chemistry/metabolism ; Lactobacillus brevis/*chemistry ; Models, Biological ; Models, Molecular ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; Pyrimidines/chemistry/metabolism ; Structure-Activity Relationship ; Substrate Specificity
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  • 74
    Publication Date: 2013-10-04
    Description: Na(+),K(+)-ATPase pumps three Na(+) ions out of cells in exchange for two K(+) taken up from the extracellular medium per ATP molecule hydrolysed, thereby establishing Na(+) and K(+) gradients across the membrane in all animal cells. These ion gradients are used in many fundamental processes, notably excitation of nerve cells. Here we describe 2.8 A-resolution crystal structures of this ATPase from pig kidney with bound Na(+), ADP and aluminium fluoride, a stable phosphate analogue, with and without oligomycin that promotes Na(+) occlusion. These crystal structures represent a transition state preceding the phosphorylated intermediate (E1P) in which three Na(+) ions are occluded. Details of the Na(+)-binding sites show how this ATPase functions as a Na(+)-specific pump, rejecting K(+) and Ca(2+), even though its affinity for Na(+) is low (millimolar dissociation constant). A mechanism for sequential, cooperative Na(+) binding can now be formulated in atomic detail.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kanai, Ryuta -- Ogawa, Haruo -- Vilsen, Bente -- Cornelius, Flemming -- Toyoshima, Chikashi -- England -- Nature. 2013 Oct 10;502(7470):201-6. doi: 10.1038/nature12578. Epub 2013 Oct 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute of Molecular and Cellular Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24089211" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Binding Sites ; Crystallography, X-Ray ; Kidney/enzymology ; *Models, Molecular ; Protein Structure, Tertiary ; Sodium/*chemistry ; Sodium-Potassium-Exchanging ATPase/*chemistry ; Swine
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  • 75
    Publication Date: 2013-09-21
    Description: Bacteria use modular polyketide synthases (PKSs) to assemble complex polyketides, many of which are leads for the development of clinical drugs, in particular anti-infectives and anti-tumoral agents. Because these multifarious compounds are notoriously difficult to synthesize, they are usually produced by microbial fermentation. During the past two decades, an impressive body of knowledge on modular PKSs has been gathered that not only provides detailed insight into the biosynthetic pathways but also allows the rational engineering of enzymatic processing lines to yield structural analogues. Notably, a hallmark of all PKS modules studied so far is the head-to-tail fusion of acyl and malonyl building blocks, which leads to linear backbones. Yet, structural diversity is limited by this uniform assembly mode. Here we demonstrate a new type of PKS module from the endofungal bacterium Burkholderia rhizoxinica that catalyses a Michael-type acetyl addition to generate a branch in the carbon chain. In vitro reconstitution of the entire PKS module, X-ray structures of a ketosynthase-branching didomain and mutagenesis experiments revealed a crucial role of the ketosynthase domain in branching the carbon chain. We present a trapped intermediary state in which acyl carrier protein and ketosynthase are covalently linked by the branched polyketide and suggest a new mechanism for chain alkylation, which is functionally distinct from terpenoid-like beta-branching. For the rice seedling blight toxin rhizoxin, one of the strongest known anti-mitotic agents, the non-canonical polyketide modification is indispensable for phytotoxic and anti-tumoral activities. We propose that the formation of related pharmacophoric groups follows the same general scheme and infer a unifying vinylogous branching reaction for PKS modules with a ketosynthase-branching-acyl-carrier-protein architecture. This study unveils the structure and function of a new PKS module that broadens the biosynthetic scope of polyketide biosynthesis and sets the stage for rationally creating structural diversity.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bretschneider, Tom -- Heim, Joel B -- Heine, Daniel -- Winkler, Robert -- Busch, Benjamin -- Kusebauch, Bjorn -- Stehle, Thilo -- Zocher, Georg -- Hertweck, Christian -- England -- Nature. 2013 Oct 3;502(7469):124-8. doi: 10.1038/nature12588. Epub 2013 Sep 18.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena 07745, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24048471" target="_blank"〉PubMed〈/a〉
    Keywords: Burkholderia/chemistry/*enzymology/genetics ; Catalysis ; Crystallography, X-Ray ; Lactones/metabolism ; Macrolides/chemistry ; *Models, Molecular ; Mutagenesis ; Polyketide Synthases/genetics/*metabolism ; Protein Structure, Tertiary
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  • 76
    Publication Date: 2013-07-03
    Description: Transcription factors are frequently altered in leukaemia through chromosomal translocation, mutation or aberrant expression. AML1-ETO, a fusion protein generated by the t(8;21) translocation in acute myeloid leukaemia, is a transcription factor implicated in both gene repression and activation. AML1-ETO oligomerization, mediated by the NHR2 domain, is critical for leukaemogenesis, making it important to identify co-regulatory factors that 'read' the NHR2 oligomerization and contribute to leukaemogenesis. Here we show that, in human leukaemic cells, AML1-ETO resides in and functions through a stable AML1-ETO-containing transcription factor complex (AETFC) that contains several haematopoietic transcription (co)factors. These AETFC components stabilize the complex through multivalent interactions, provide multiple DNA-binding domains for diverse target genes, co-localize genome wide, cooperatively regulate gene expression, and contribute to leukaemogenesis. Within the AETFC complex, AML1-ETO oligomerization is required for a specific interaction between the oligomerized NHR2 domain and a novel NHR2-binding (N2B) motif in E proteins. Crystallographic analysis of the NHR2-N2B complex reveals a unique interaction pattern in which an N2B peptide makes direct contact with side chains of two NHR2 domains as a dimer, providing a novel model of how dimeric/oligomeric transcription factors create a new protein-binding interface through dimerization/oligomerization. Intriguingly, disruption of this interaction by point mutations abrogates AML1-ETO-induced haematopoietic stem/progenitor cell self-renewal and leukaemogenesis. These results reveal new mechanisms of action of AML1-ETO, and provide a potential therapeutic target in t(8;21)-positive acute myeloid leukaemia.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3732535/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3732535/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sun, Xiao-Jian -- Wang, Zhanxin -- Wang, Lan -- Jiang, Yanwen -- Kost, Nils -- Soong, T David -- Chen, Wei-Yi -- Tang, Zhanyun -- Nakadai, Tomoyoshi -- Elemento, Olivier -- Fischle, Wolfgang -- Melnick, Ari -- Patel, Dinshaw J -- Nimer, Stephen D -- Roeder, Robert G -- CA113872/CA/NCI NIH HHS/ -- CA129325/CA/NCI NIH HHS/ -- CA163086/CA/NCI NIH HHS/ -- CA166835/CA/NCI NIH HHS/ -- R01 CA163086/CA/NCI NIH HHS/ -- R01 CA166835/CA/NCI NIH HHS/ -- UL1 RR024143/RR/NCRR NIH HHS/ -- UL1RR024143/RR/NCRR NIH HHS/ -- England -- Nature. 2013 Aug 1;500(7460):93-7. doi: 10.1038/nature12287. Epub 2013 Jun 30.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, New York 10065, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23812588" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Amino Acid Sequence ; Animals ; Binding Sites ; Cell Division ; Cell Line, Tumor ; *Cell Transformation, Neoplastic/genetics ; Core Binding Factor Alpha 2 Subunit/chemistry/*metabolism ; Hematopoietic Stem Cells/cytology/metabolism/pathology ; Humans ; Leukemia, Myeloid, Acute/genetics/*metabolism/*pathology ; Mice ; Models, Molecular ; Molecular Sequence Data ; Multiprotein Complexes/chemistry/*metabolism ; Oncogene Proteins, Fusion/chemistry/*metabolism ; Point Mutation ; Protein Binding ; Protein Multimerization ; Protein Stability ; Protein Structure, Tertiary ; Transcription Factors/*metabolism
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  • 77
    Publication Date: 2013-03-23
    Description: 〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3694752/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3694752/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Levy, Colin -- Zoltowski, Brian D -- Jones, Alex R -- Vaidya, Anand T -- Top, Deniz -- Widom, Joanne -- Young, Michael W -- Scrutton, Nigel S -- Crane, Brian R -- Leys, David -- R01 GM079679/GM/NIGMS NIH HHS/ -- R37 GM054339/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Mar 21;495(7441):E3-4. doi: 10.1038/nature11995.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23518567" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Cryptochromes/chemistry ; Drosophila/*chemistry ; *Models, Molecular ; Protein Structure, Tertiary
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  • 78
    Publication Date: 2013-09-03
    Description: Sodium/proton (Na(+)/H(+)) antiporters, located at the plasma membrane in every cell, are vital for cell homeostasis. In humans, their dysfunction has been linked to diseases, such as hypertension, heart failure and epilepsy, and they are well-established drug targets. The best understood model system for Na(+)/H(+) antiport is NhaA from Escherichia coli, for which both electron microscopy and crystal structures are available. NhaA is made up of two distinct domains: a core domain and a dimerization domain. In the NhaA crystal structure a cavity is located between the two domains, providing access to the ion-binding site from the inward-facing surface of the protein. Like many Na(+)/H(+) antiporters, the activity of NhaA is regulated by pH, only becoming active above pH 6.5, at which point a conformational change is thought to occur. The only reported NhaA crystal structure so far is of the low pH inactivated form. Here we describe the active-state structure of a Na(+)/H(+) antiporter, NapA from Thermus thermophilus, at 3 A resolution, solved from crystals grown at pH 7.8. In the NapA structure, the core and dimerization domains are in different positions to those seen in NhaA, and a negatively charged cavity has now opened to the outside. The extracellular cavity allows access to a strictly conserved aspartate residue thought to coordinate ion binding directly, a role supported here by molecular dynamics simulations. To alternate access to this ion-binding site, however, requires a surprisingly large rotation of the core domain, some 20 degrees against the dimerization interface. We conclude that despite their fast transport rates of up to 1,500 ions per second, Na(+)/H(+) antiporters operate by a two-domain rocking bundle model, revealing themes relevant to secondary-active transporters in general.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3914025/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3914025/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lee, Chiara -- Kang, Hae Joo -- von Ballmoos, Christoph -- Newstead, Simon -- Uzdavinys, Povilas -- Dotson, David L -- Iwata, So -- Beckstein, Oliver -- Cameron, Alexander D -- Drew, David -- 062164/Z/00/Z/Wellcome Trust/United Kingdom -- 099165/Wellcome Trust/United Kingdom -- BB/G02325/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- BB/G023425/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- G0900399/Medical Research Council/United Kingdom -- G0900990/Medical Research Council/United Kingdom -- England -- Nature. 2013 Sep 26;501(7468):573-7. doi: 10.1038/nature12484. Epub 2013 Sep 1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Molecular Biosciences, Imperial College London, London SW7 2AZ, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23995679" target="_blank"〉PubMed〈/a〉
    Keywords: Aspartic Acid/chemistry/metabolism ; Binding Sites ; Crystallography, X-Ray ; Escherichia coli Proteins/chemistry ; Hydrogen-Ion Concentration ; Models, Molecular ; Molecular Dynamics Simulation ; Protein Multimerization ; Protein Structure, Tertiary ; Protons ; Sodium/metabolism ; Sodium-Hydrogen Antiporter/*chemistry/genetics/metabolism ; Static Electricity ; Thermus thermophilus/*chemistry/genetics
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  • 79
    Publication Date: 2013-03-15
    Description: The hepatocyte nuclear factor 4alpha (HNF-4alpha; also known as NR2A1) is a member of the nuclear receptor (NR) family of transcription factors, which have conserved DNA-binding domains and ligand-binding domains. HNF-4alpha is the most abundant DNA-binding protein in the liver, where some 40% of the actively transcribed genes have a HNF-4alpha response element. These regulated genes are largely involved in the hepatic gluconeogenic program and lipid metabolism. In the pancreas HNF-4alpha is also a master regulator, controlling an estimated 11% of islet genes. HNF-4alpha protein mutations are linked to maturity-onset diabetes of the young, type 1 (MODY1) and hyperinsulinaemic hypoglycaemia. Previous structural analyses of NRs, although productive in elucidating the structure of individual domains, have lagged behind in revealing the connectivity patterns of NR domains. Here we describe the 2.9 A crystal structure of the multidomain human HNF-4alpha homodimer bound to its DNA response element and coactivator-derived peptides. A convergence zone connects multiple receptor domains in an asymmetric fashion, joining distinct elements from each monomer. An arginine target of PRMT1 methylation protrudes directly into this convergence zone and sustains its integrity. A serine target of protein kinase C is also responsible for maintaining domain-domain interactions. These post-translational modifications lead to changes in DNA binding by communicating through the tightly connected surfaces of the quaternary fold. We find that some MODY1 mutations, positioned on the ligand-binding domain and hinge regions of the receptor, compromise DNA binding at a distance by communicating through the interjunctional surfaces of the complex. The overall domain representation of the HNF-4alpha homodimer is different from that of the PPAR-gamma-RXR-alpha heterodimer, even when both NR complexes are assembled on the same DNA element. Our findings suggest that unique quaternary folds and interdomain connections in NRs could be exploited by small-molecule allosteric modulators that affect distal functions in these polypeptides.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3606643/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3606643/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Chandra, Vikas -- Huang, Pengxiang -- Potluri, Nalini -- Wu, Dalei -- Kim, Youngchang -- Rastinejad, Fraydoon -- R01 DK094147/DK/NIDDK NIH HHS/ -- R01 DK097475/DK/NIDDK NIH HHS/ -- England -- Nature. 2013 Mar 21;495(7441):394-8. doi: 10.1038/nature11966. Epub 2013 Mar 13.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Metabolic Signaling and Disease Program, Sanford-Burnham Medical Research Institute, Orlando, Florida 32827, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23485969" target="_blank"〉PubMed〈/a〉
    Keywords: Hepatocyte Nuclear Factor 4/*chemistry/genetics/metabolism ; Humans ; Hypoglycemia/genetics ; *Models, Molecular ; Mutation ; Point Mutation ; Protein Binding ; Protein Structure, Quaternary ; Protein Structure, Tertiary
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  • 80
    Publication Date: 2013-04-20
    Description: TrkH belongs to a superfamily of K(+) transport proteins required for growth of bacteria in low external K(+) concentrations. The crystal structure of TrkH from Vibrio parahaemolyticus showed that TrkH resembles a K(+) channel and may have a gating mechanism substantially different from K(+) channels. TrkH assembles with TrkA, a cytosolic protein comprising two RCK (regulate the conductance of K(+)) domains, which are found in certain K(+) channels and control their gating. However, fundamental questions on whether TrkH is an ion channel and how it is regulated by TrkA remain unresolved. Here we show single-channel activity of TrkH that is upregulated by ATP via TrkA. We report two structures of the tetrameric TrkA ring, one in complex with TrkH and one in isolation, in which the ring assumes two markedly different conformations. These results suggest a mechanism for how ATP increases TrkH activity by inducing conformational changes in TrkA.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3726529/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3726529/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Cao, Yu -- Pan, Yaping -- Huang, Hua -- Jin, Xiangshu -- Levin, Elena J -- Kloss, Brian -- Zhou, Ming -- DK088057/DK/NIDDK NIH HHS/ -- GM098878/GM/NIGMS NIH HHS/ -- HL086392/HL/NHLBI NIH HHS/ -- R01 DK088057/DK/NIDDK NIH HHS/ -- R01 GM098878/GM/NIGMS NIH HHS/ -- R01 HL086392/HL/NHLBI NIH HHS/ -- U54 GM075026/GM/NIGMS NIH HHS/ -- U54 GM095315/GM/NIGMS NIH HHS/ -- U54GM095315/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Apr 18;496(7445):317-22. doi: 10.1038/nature12056.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology & Cellular Biophysics, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, New York 10032, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23598339" target="_blank"〉PubMed〈/a〉
    Keywords: Adenosine Diphosphate/metabolism ; Adenosine Triphosphate/metabolism ; Bacterial Proteins/*chemistry/*metabolism ; Crystallography, X-Ray ; Electric Conductivity ; *Ion Channel Gating ; Ion Transport ; Models, Molecular ; Protein Folding ; Protein Structure, Quaternary ; Protein Structure, Tertiary ; Vibrio parahaemolyticus
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  • 81
    Publication Date: 2013-04-05
    Description: Telomerase adds telomeric repeats to chromosome ends using an internal RNA template and a specialized telomerase reverse transcriptase (TERT), thereby maintaining genome integrity. Little is known about the physical relationships among protein and RNA subunits within a biologically functional holoenzyme. Here we describe the architecture of Tetrahymena thermophila telomerase holoenzyme determined by electron microscopy. Six of the seven proteins and the TERT-binding regions of telomerase RNA (TER) have been localized by affinity labelling. Fitting with high-resolution structures reveals the organization of TERT, TER and p65 in the ribonucleoprotein (RNP) catalytic core. p50 has an unanticipated role as a hub between the RNP catalytic core, p75-p19-p45 subcomplex, and the DNA-binding Teb1. A complete in vitro holoenzyme reconstitution assigns function to these interactions in processive telomeric repeat synthesis. These studies provide the first view of the extensive network of subunit associations necessary for telomerase holoenzyme assembly and physiological function.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3817743/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3817743/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Jiang, Jiansen -- Miracco, Edward J -- Hong, Kyungah -- Eckert, Barbara -- Chan, Henry -- Cash, Darian D -- Min, Bosun -- Zhou, Z Hong -- Collins, Kathleen -- Feigon, Juli -- AI069015/AI/NIAID NIH HHS/ -- F32 GM101874/GM/NIGMS NIH HHS/ -- GM007185/GM/NIGMS NIH HHS/ -- GM071940/GM/NIGMS NIH HHS/ -- GM101874/GM/NIGMS NIH HHS/ -- GM48123/GM/NIGMS NIH HHS/ -- GM54198/GM/NIGMS NIH HHS/ -- R01 GM048123/GM/NIGMS NIH HHS/ -- R01 GM054198/GM/NIGMS NIH HHS/ -- R01 GM071940/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Apr 11;496(7444):187-92. doi: 10.1038/nature12062. Epub 2013 Apr 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, California 90095, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23552895" target="_blank"〉PubMed〈/a〉
    Keywords: Catalytic Domain ; Holoenzymes/chemistry/genetics/ultrastructure ; Microscopy, Electron ; Models, Molecular ; Nucleic Acid Conformation ; Pliability ; Protein Structure, Tertiary ; Protein Subunits/analysis/chemistry/metabolism ; Protozoan Proteins/chemistry/metabolism/ultrastructure ; RNA/chemistry/metabolism/ultrastructure ; Ribonucleoproteins/chemistry/genetics/metabolism/ultrastructure ; Telomerase/*chemistry/genetics/metabolism/*ultrastructure ; Tetrahymena thermophila/chemistry/*enzymology/genetics/ultrastructure
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  • 82
    Publication Date: 2013-12-07
    Description: Human GABA(B) (gamma-aminobutyric acid class B) receptor is a G-protein-coupled receptor central to inhibitory neurotransmission in the brain. It functions as an obligatory heterodimer of the subunits GBR1 and GBR2. Here we present the crystal structures of a heterodimeric complex between the extracellular domains of GBR1 and GBR2 in the apo, agonist-bound and antagonist-bound forms. The apo and antagonist-bound structures represent the resting state of the receptor; the agonist-bound complex corresponds to the active state. Both subunits adopt an open conformation at rest, and only GBR1 closes on agonist-induced receptor activation. The agonists and antagonists are anchored in the interdomain crevice of GBR1 by an overlapping set of residues. An antagonist confines GBR1 to the open conformation of the inactive state, whereas an agonist induces its domain closure for activation. Our data reveal a unique activation mechanism for GABA(B) receptor that involves the formation of a novel heterodimer interface between subunits.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3865065/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3865065/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Geng, Yong -- Bush, Martin -- Mosyak, Lidia -- Wang, Feng -- Fan, Qing R -- R01 GM088454/GM/NIGMS NIH HHS/ -- R01GM088454/GM/NIGMS NIH HHS/ -- England -- Nature. 2013 Dec 12;504(7479):254-9. doi: 10.1038/nature12725. Epub 2013 Dec 4.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pharmacology, Columbia University, New York, New York 10032, USA. ; 1] Department of Pharmacology, Columbia University, New York, New York 10032, USA [2] Department of Pathology & Cell Biology, Columbia University, New York, New York 10032, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24305054" target="_blank"〉PubMed〈/a〉
    Keywords: Apoproteins/chemistry/metabolism ; Binding Sites ; Crystallography, X-Ray ; Disulfides/chemistry/metabolism ; GABA-B Receptor Agonists/pharmacology ; GABA-B Receptor Antagonists/pharmacology ; Humans ; Ligands ; Models, Molecular ; Protein Multimerization ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; Receptors, GABA-B/*chemistry/*metabolism ; Substrate Specificity
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  • 83
    Publication Date: 2013-07-09
    Description: Protein folding is often described as a search process, in which polypeptides explore different conformations to find their native structure. Molecular chaperones are known to improve folding yields by suppressing aggregation between polypeptides before this conformational search starts, as well as by rescuing misfolds after it ends. Although chaperones have long been speculated to also affect the conformational search itself--by reshaping the underlying folding landscape along the folding trajectory--direct experimental evidence has been scarce so far. In Escherichia coli, the general chaperone trigger factor (TF) could play such a role. TF has been shown to interact with nascent chains at the ribosome, with polypeptides released from the ribosome into the cytosol, and with fully folded proteins before their assembly into larger complexes. To investigate the effect of TF from E. coli on the conformational search of polypeptides to their native state, we investigated individual maltose binding protein (MBP) molecules using optical tweezers. Here we show that TF binds folded structures smaller than one domain, which are then stable for seconds and ultimately convert to the native state. Moreover, TF stimulates native folding in constructs of repeated MBP domains. The results indicate that TF promotes correct folding by protecting partially folded states from distant interactions that produce stable misfolded states. As TF interacts with most newly synthesized proteins in E. coli, we expect these findings to be of general importance in understanding protein folding pathways.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mashaghi, Alireza -- Kramer, Gunter -- Bechtluft, Philipp -- Zachmann-Brand, Beate -- Driessen, Arnold J M -- Bukau, Bernd -- Tans, Sander J -- England -- Nature. 2013 Aug 1;500(7460):98-101. doi: 10.1038/nature12293. Epub 2013 Jul 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉FOM institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23831649" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Cytosol/metabolism ; Escherichia coli/chemistry/metabolism ; Escherichia coli Proteins/*metabolism ; Maltose-Binding Proteins/biosynthesis/*chemistry/*metabolism ; Models, Molecular ; Molecular Chaperones/*metabolism ; Optical Tweezers ; Peptides/chemistry/metabolism ; Peptidylprolyl Isomerase/*metabolism ; Protein Biosynthesis ; Protein Conformation ; *Protein Folding ; Protein Refolding ; Protein Stability ; Protein Structure, Tertiary ; Ribosomes/metabolism ; Spectroscopy, Fourier Transform Infrared
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  • 84
    Publication Date: 2013-04-09
    Description: TET (ten-eleven-translocation) proteins are Fe(ii)- and alpha-ketoglutarate-dependent dioxygenases that modify the methylation status of DNA by successively oxidizing 5-methylcytosine to 5-hydroxymethylcytosine, 5-formylcytosine and 5-carboxycytosine, potential intermediates in the active erasure of DNA-methylation marks. Here we show that IDAX (also known as CXXC4), a reported inhibitor of Wnt signalling that has been implicated in malignant renal cell carcinoma and colonic villous adenoma, regulates TET2 protein expression. IDAX was originally encoded within an ancestral TET2 gene that underwent a chromosomal gene inversion during evolution, thus separating the TET2 CXXC domain from the catalytic domain. The IDAX CXXC domain binds DNA sequences containing unmethylated CpG dinucleotides, localizes to promoters and CpG islands in genomic DNA and interacts directly with the catalytic domain of TET2. Unexpectedly, IDAX expression results in caspase activation and TET2 protein downregulation, in a manner that depends on DNA binding through the IDAX CXXC domain, suggesting that IDAX recruits TET2 to DNA before degradation. IDAX depletion prevents TET2 downregulation in differentiating mouse embryonic stem cells, and short hairpin RNA against IDAX increases TET2 protein expression in the human monocytic cell line U937. Notably, we find that the expression and activity of TET3 is also regulated through its CXXC domain. Taken together, these results establish the separate and linked CXXC domains of TET2 and TET3, respectively, as previously unknown regulators of caspase activation and TET enzymatic activity.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3643997/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3643997/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ko, Myunggon -- An, Jungeun -- Bandukwala, Hozefa S -- Chavez, Lukas -- Aijo, Tarmo -- Pastor, William A -- Segal, Matthew F -- Li, Huiming -- Koh, Kian Peng -- Lahdesmaki, Harri -- Hogan, Patrick G -- Aravind, L -- Rao, Anjana -- CA151535/CA/NCI NIH HHS/ -- R01 AI040127/AI/NIAID NIH HHS/ -- R01 AI044432/AI/NIAID NIH HHS/ -- R01 AI40127/AI/NIAID NIH HHS/ -- R01 CA151535/CA/NCI NIH HHS/ -- R01 HD065812/HD/NICHD NIH HHS/ -- England -- Nature. 2013 May 2;497(7447):122-6. doi: 10.1038/nature12052. Epub 2013 Apr 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Signaling and Gene Expression, La Jolla Institute for Allergy & Immunology, La Jolla, California 92037, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23563267" target="_blank"〉PubMed〈/a〉
    Keywords: 5-Methylcytosine/*metabolism ; Animals ; Base Sequence ; Caspases/metabolism ; Catalytic Domain ; CpG Islands/genetics ; DNA Methylation/genetics ; DNA-Binding Proteins/biosynthesis/*chemistry/deficiency/genetics/*metabolism ; Dioxygenases/chemistry/genetics/metabolism ; Down-Regulation ; Embryonic Stem Cells/metabolism ; Enzyme Activation ; HEK293 Cells ; Humans ; Mice ; Oxidation-Reduction ; Promoter Regions, Genetic/genetics ; Protein Interaction Domains and Motifs ; Protein Structure, Tertiary ; Proto-Oncogene Proteins/biosynthesis/chemistry/genetics/*metabolism ; Transcription Factors/*chemistry/deficiency/genetics/*metabolism ; U937 Cells
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  • 85
    Publication Date: 2012-03-16
    Description: Derivatives of vitamin B(12) are used in methyl group transfer in biological processes as diverse as methionine synthesis in humans and CO(2) fixation in acetogenic bacteria. This seemingly straightforward reaction requires large, multimodular enzyme complexes that adopt multiple conformations to alternately activate, protect and perform catalysis on the reactive B(12) cofactor. Crystal structures determined thus far have provided structural information for only fragments of these complexes, inspiring speculation about the overall protein assembly and conformational movements inherent to activity. Here we present X-ray crystal structures of a complete 220 kDa complex that contains all enzymes responsible for B(12)-dependent methyl transfer, namely the corrinoid iron-sulphur protein and its methyltransferase from the model acetogen Moorella thermoacetica. These structures provide the first three-dimensional depiction of all protein modules required for the activation, protection and catalytic steps of B(12)-dependent methyl transfer. In addition, the structures capture B(12) at multiple locations between its 'resting' and catalytic positions, allowing visualization of the dramatic protein rearrangements that enable methyl transfer and identification of the trajectory for B(12) movement within the large enzyme scaffold. The structures are also presented alongside in crystallo spectroscopic data, which confirm enzymatic activity within crystals and demonstrate the largest known conformational movements of proteins in a crystalline state. Taken together, this work provides a model for the molecular juggling that accompanies turnover and helps explain why such an elaborate protein framework is required for such a simple, yet biologically essential reaction.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3326194/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3326194/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kung, Yan -- Ando, Nozomi -- Doukov, Tzanko I -- Blasiak, Leah C -- Bender, Gunes -- Seravalli, Javier -- Ragsdale, Stephen W -- Drennan, Catherine L -- GM39451/GM/NIGMS NIH HHS/ -- GM69857/GM/NIGMS NIH HHS/ -- R01 GM039451/GM/NIGMS NIH HHS/ -- R01 GM039451-25/GM/NIGMS NIH HHS/ -- R01 GM069857/GM/NIGMS NIH HHS/ -- R37 GM039451/GM/NIGMS NIH HHS/ -- RR-15301/RR/NCRR NIH HHS/ -- T32 GM008334/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2012 Mar 14;484(7393):265-9. doi: 10.1038/nature10916.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22419154" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Biocatalysis ; Corrinoids/metabolism ; Crystallography, X-Ray ; Folic Acid/metabolism ; Iron-Sulfur Proteins/*chemistry/*metabolism ; Methylation ; Methyltransferases/*chemistry/*metabolism ; Models, Biological ; Models, Molecular ; Moorella/chemistry/*enzymology ; Protein Multimerization ; Protein Structure, Tertiary ; Vitamin B 12/*metabolism
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  • 86
    Publication Date: 2012-10-23
    Description: The single-component type-II NADH dehydrogenases (NDH-2s) serve as alternatives to the multisubunit respiratory complex I (type-I NADH dehydrogenase (NDH-1), also called NADH:ubiquinone oxidoreductase; EC 1.6.5.3) in catalysing electron transfer from NADH to ubiquinone in the mitochondrial respiratory chain. The yeast NDH-2 (Ndi1) oxidizes NADH on the matrix side and reduces ubiquinone to maintain mitochondrial NADH/NAD(+) homeostasis. Ndi1 is a potential therapeutic agent for human diseases caused by complex I defects, particularly Parkinson's disease, because its expression restores the mitochondrial activity in animals with complex I deficiency. NDH-2s in pathogenic microorganisms are viable targets for new antibiotics. Here we solve the crystal structures of Ndi1 in its substrate-free, NADH-, ubiquinone- and NADH-ubiquinone-bound states, to help understand the catalytic mechanism of NDH-2s. We find that Ndi1 homodimerization through its carboxy-terminal domain is critical for its catalytic activity and membrane targeting. The structures reveal two ubiquinone-binding sites (UQ(I) and UQ(II)) in Ndi1. NADH and UQ(I) can bind to Ndi1 simultaneously to form a substrate-protein complex. We propose that UQ(I) interacts with FAD to act as an intermediate for electron transfer, and that NADH transfers electrons through this FAD-UQ(I) complex to UQ(II). Together our data reveal the regulatory and catalytic mechanisms of Ndi1 and may facilitate the development or targeting of NDH-2s for potential therapeutic applications.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Feng, Yue -- Li, Wenfei -- Li, Jian -- Wang, Jiawei -- Ge, Jingpeng -- Xu, Duo -- Liu, Yanjing -- Wu, Kaiqi -- Zeng, Qingyin -- Wu, Jia-Wei -- Tian, Changlin -- Zhou, Bing -- Yang, Maojun -- England -- Nature. 2012 Nov 15;491(7424):478-82. doi: 10.1038/nature11541. Epub 2012 Oct 21.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉State Key Laboratory of Biomembrane and Membrane Biotechnology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23086143" target="_blank"〉PubMed〈/a〉
    Keywords: Crystallography, X-Ray ; Electron Transport Complex I/*chemistry/isolation & purification/metabolism ; Mitochondria/*enzymology ; *Models, Molecular ; NAD/chemistry ; Protein Binding ; Protein Multimerization ; Protein Structure, Tertiary ; Saccharomyces cerevisiae/chemistry/enzymology ; Saccharomyces cerevisiae Proteins/*chemistry/isolation & purification/metabolism ; Ubiquinone/chemistry
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  • 87
    Publication Date: 2012-12-04
    Description: Mechanisms of protein recognition have been extensively studied for single-domain proteins, but are less well characterized for dynamic multidomain systems. Ubiquitin chains represent a biologically important multidomain system that requires recognition by structurally diverse ubiquitin-interacting proteins. Ubiquitin chain conformations in isolation are often different from conformations observed in ubiquitin-interacting protein complexes, indicating either great dynamic flexibility or extensive chain remodelling upon binding. Using single-molecule fluorescence resonance energy transfer, we show that Lys 63-, Lys 48- and Met 1-linked diubiquitin exist in several distinct conformational states in solution. Lys 63- and Met 1-linked diubiquitin adopt extended 'open' and more compact 'closed' conformations, and ubiquitin-binding domains and deubiquitinases (DUBs) select pre-existing conformations. By contrast, Lys 48-linked diubiquitin adopts predominantly compact conformations. DUBs directly recognize existing conformations, but may also remodel ubiquitin chains to hydrolyse the isopeptide bond. Disruption of the Lys 48-diubiquitin interface changes conformational dynamics and affects DUB activity. Hence, conformational equilibria in ubiquitin chains provide an additional layer of regulation in the ubiquitin system, and distinct conformations observed in differently linked polyubiquitin may contribute to the specificity of ubiquitin-interacting proteins.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3605796/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3605796/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ye, Yu -- Blaser, Georg -- Horrocks, Mathew H -- Ruedas-Rama, Maria J -- Ibrahim, Shehu -- Zhukov, Alexander A -- Orte, Angel -- Klenerman, David -- Jackson, Sophie E -- Komander, David -- 092096/Wellcome Trust/United Kingdom -- BB/F00219X/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- MC_U105192732/Medical Research Council/United Kingdom -- U.1051.03.019.00001.01(92732)/Medical Research Council/United Kingdom -- U105192732/Medical Research Council/United Kingdom -- Biotechnology and Biological Sciences Research Council/United Kingdom -- England -- Nature. 2012 Dec 13;492(7428):266-70. doi: 10.1038/nature11722. Epub 2012 Dec 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Protein and Nucleic Acids Chemistry, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23201676" target="_blank"〉PubMed〈/a〉
    Keywords: Fluorescence Resonance Energy Transfer ; *Models, Molecular ; Protein Binding ; Protein Structure, Tertiary ; Ubiquitin/*chemistry/*metabolism
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  • 88
    Publication Date: 2012-11-13
    Description: Chromatin-remodelling complexes (CRCs) mobilize nucleosomes to mediate the access of DNA-binding factors to their sites in vivo. These CRCs contain a catalytic subunit that bears an ATPase/DNA-translocase domain and flanking regions that bind nucleosomal epitopes. A central question is whether and how these flanking regions regulate ATP hydrolysis or the coupling of hydrolysis to DNA translocation, to affect nucleosome-sliding efficiency. ISWI-family CRCs contain the protein ISWI, which uses its ATPase/DNA-translocase domain to pump DNA around the histone octamer to enable sliding. ISWI is positively regulated by two 'activating' nucleosomal epitopes: the 'basic patch' on the histone H4 tail, and extranucleosomal (linker) DNA. Previous work defined the HAND-SANT-SLIDE (HSS) domain at the ISWI carboxy terminus that binds linker DNA, needed for ISWI activity. Here we define two new, conserved and separate regulatory regions on Drosophila ISWI, termed AutoN and NegC, which negatively regulate ATP hydrolysis (AutoN) or the coupling of ATP hydrolysis to productive DNA translocation (NegC). The two aforementioned nucleosomal epitopes promote remodelling indirectly by preventing the negative regulation of AutoN and NegC. Notably, mutation or removal of AutoN and NegC enables marked nucleosome sliding without the H4 basic patch or extranucleosomal DNA, or the HSS domain, conferring on ISWI the biochemical attributes normally associated with SWI/SNF-family ATPases. Thus, the ISWI ATPase catalytic core is an intrinsically active DNA translocase that conducts nucleosome sliding, onto which selective 'inhibition-of-inhibition' modules are placed, to help ensure that remodelling occurs only in the presence of proper nucleosomal epitopes. This supports a general concept for the specialization of chromatin-remodelling ATPases, in which specific regulatory modules adapt an ancient active DNA translocase to conduct particular tasks only on the appropriate chromatin landscape.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3631562/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3631562/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Clapier, Cedric R -- Cairns, Bradley R -- CA042014/CA/NCI NIH HHS/ -- GM60415/GM/NIGMS NIH HHS/ -- R01 GM060415/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2012 Dec 13;492(7428):280-4. doi: 10.1038/nature11625. Epub 2012 Nov 11.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Howard Hughes Medical Institute and Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA. cedric.clapier@hci.utah.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23143334" target="_blank"〉PubMed〈/a〉
    Keywords: Adenosine Triphosphatases/chemistry/*genetics/*metabolism ; Adenosine Triphosphate/metabolism ; Amino Acid Sequence ; Animals ; Chromatin Assembly and Disassembly ; Drosophila Proteins/chemistry/genetics/metabolism ; Drosophila melanogaster/enzymology/*genetics/*metabolism ; Epitopes/*metabolism ; *Gene Expression Regulation ; Hydrolysis ; Models, Molecular ; Molecular Sequence Data ; Mutation ; Nucleosomes/*metabolism ; Protein Binding ; Protein Structure, Tertiary ; Regulatory Sequences, Nucleic Acid/genetics ; Sequence Alignment ; Transcription Factors/chemistry/*genetics/*metabolism
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  • 89
    Publication Date: 2012-06-23
    Description: The assembly of retroviruses such as HIV-1 is driven by oligomerization of their major structural protein, Gag. Gag is a multidomain polyprotein including three conserved folded domains: MA (matrix), CA (capsid) and NC (nucleocapsid). Assembly of an infectious virion proceeds in two stages. In the first stage, Gag oligomerization into a hexameric protein lattice leads to the formation of an incomplete, roughly spherical protein shell that buds through the plasma membrane of the infected cell to release an enveloped immature virus particle. In the second stage, cleavage of Gag by the viral protease leads to rearrangement of the particle interior, converting the non-infectious immature virus particle into a mature infectious virion. The immature Gag shell acts as the pivotal intermediate in assembly and is a potential target for anti-retroviral drugs both in inhibiting virus assembly and in disrupting virus maturation. However, detailed structural information on the immature Gag shell has not previously been available. For this reason it is unclear what protein conformations and interfaces mediate the interactions between domains and therefore the assembly of retrovirus particles, and what structural transitions are associated with retrovirus maturation. Here we solve the structure of the immature retroviral Gag shell from Mason-Pfizer monkey virus by combining cryo-electron microscopy and tomography. The 8-A resolution structure permits the derivation of a pseudo-atomic model of CA in the immature retrovirus, which defines the protein interfaces mediating retrovirus assembly. We show that transition of an immature retrovirus into its mature infectious form involves marked rotations and translations of CA domains, that the roles of the amino-terminal and carboxy-terminal domains of CA in assembling the immature and mature hexameric lattices are exchanged, and that the CA interactions that stabilize the immature and mature viruses are almost completely distinct.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bharat, Tanmay A M -- Davey, Norman E -- Ulbrich, Pavel -- Riches, James D -- de Marco, Alex -- Rumlova, Michaela -- Sachse, Carsten -- Ruml, Tomas -- Briggs, John A G -- England -- Nature. 2012 Jul 19;487(7407):385-9. doi: 10.1038/nature11169.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22722831" target="_blank"〉PubMed〈/a〉
    Keywords: Capsid/metabolism/*ultrastructure ; *Cryoelectron Microscopy ; Mason-Pfizer monkey virus/*ultrastructure ; *Models, Molecular ; Protein Structure, Tertiary ; Virus Assembly
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  • 90
    Publication Date: 2012-11-16
    Description: Characterization of human monoclonal antibodies is providing considerable insight into mechanisms of broad HIV-1 neutralization. Here we report an HIV-1 gp41 membrane-proximal external region (MPER)-specific antibody, named 10E8, which neutralizes approximately 98% of tested viruses. An analysis of sera from 78 healthy HIV-1-infected donors demonstrated that 27% contained MPER-specific antibodies and 8% contained 10E8-like specificities. In contrast to other neutralizing MPER antibodies, 10E8 did not bind phospholipids, was not autoreactive, and bound cell-surface envelope. The structure of 10E8 in complex with the complete MPER revealed a site of vulnerability comprising a narrow stretch of highly conserved gp41-hydrophobic residues and a critical arginine or lysine just before the transmembrane region. Analysis of resistant HIV-1 variants confirmed the importance of these residues for neutralization. The highly conserved MPER is a target of potent, non-self-reactive neutralizing antibodies, suggesting that HIV-1 vaccines should aim to induce antibodies to this region of HIV-1 envelope glycoprotein.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Huang, Jinghe -- Ofek, Gilad -- Laub, Leo -- Louder, Mark K -- Doria-Rose, Nicole A -- Longo, Nancy S -- Imamichi, Hiromi -- Bailer, Robert T -- Chakrabarti, Bimal -- Sharma, Shailendra K -- Alam, S Munir -- Wang, Tao -- Yang, Yongping -- Zhang, Baoshan -- Migueles, Stephen A -- Wyatt, Richard -- Haynes, Barton F -- Kwong, Peter D -- Mascola, John R -- Connors, Mark -- HSN261200800001E/PHS HHS/ -- Intramural NIH HHS/ -- England -- Nature. 2012 Nov 15;491(7424):406-12. doi: 10.1038/nature11544. Epub 2012 Sep 18.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉HIV-Specific Immunity Section, Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23151583" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Substitution ; Antibodies, Neutralizing/chemistry/*metabolism ; Antibody Specificity ; Cells, Cultured ; HEK293 Cells ; HIV Antibodies/chemistry/isolation & purification/*metabolism ; HIV Envelope Protein gp41/chemistry/*immunology ; HIV-1/*physiology ; Humans ; Models, Molecular ; Molecular Sequence Data ; Protein Binding ; Protein Structure, Tertiary
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  • 91
    Publication Date: 2012-10-23
    Description: Calcium ions (Ca(2+)) have an important role as secondary messengers in numerous signal transduction processes, and cells invest much energy in controlling and maintaining a steep gradient between intracellular ( approximately 0.1-micromolar) and extracellular ( approximately 2-millimolar) Ca(2+) concentrations. Calmodulin-stimulated calcium pumps, which include the plasma-membrane Ca(2+)-ATPases (PMCAs), are key regulators of intracellular Ca(2+) in eukaryotes. They contain a unique amino- or carboxy-terminal regulatory domain responsible for autoinhibition, and binding of calcium-loaded calmodulin to this domain releases autoinhibition and activates the pump. However, the structural basis for the activation mechanism is unknown and a key remaining question is how calmodulin-mediated PMCA regulation can cover both basal Ca(2+) levels in the nanomolar range as well as micromolar-range Ca(2+) transients generated by cell stimulation. Here we present an integrated study combining the determination of the high-resolution crystal structure of a PMCA regulatory-domain/calmodulin complex with in vivo characterization and biochemical, biophysical and bioinformatics data that provide mechanistic insights into a two-step PMCA activation mechanism mediated by calcium-loaded calmodulin. The structure shows the entire PMCA regulatory domain and reveals an unexpected 2:1 stoichiometry with two calcium-loaded calmodulin molecules binding to different sites on a long helix. A multifaceted characterization of the role of both sites leads to a general structural model for calmodulin-mediated regulation of PMCAs that allows stringent, highly responsive control of intracellular calcium in eukaryotes, making it possible to maintain a stable, basal level at a threshold Ca(2+) concentration, where steep activation occurs.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Tidow, Henning -- Poulsen, Lisbeth R -- Andreeva, Antonina -- Knudsen, Michael -- Hein, Kim L -- Wiuf, Carsten -- Palmgren, Michael G -- Nissen, Poul -- MC_U105192716/Medical Research Council/United Kingdom -- England -- Nature. 2012 Nov 15;491(7424):468-72. doi: 10.1038/nature11539. Epub 2012 Oct 21.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Centre for Membrane Pumps in Cells and Disease - PUMPKIN, Aarhus University, Gustav Wieds Vej 10c, DK-8000 Aarhus C, Denmark.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23086147" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Arabidopsis/chemistry/enzymology/*metabolism ; Arabidopsis Proteins/*chemistry/genetics/*metabolism ; Binding Sites ; Calcium/*metabolism ; Calcium-Transporting ATPases/*chemistry/genetics/*metabolism ; Calmodulin/*chemistry/metabolism ; Enzyme Activation ; Eukaryota/*metabolism ; Intracellular Space/chemistry/metabolism ; Models, Molecular ; Molecular Sequence Data ; Protein Binding ; Protein Structure, Tertiary ; Sequence Alignment
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  • 92
    Publication Date: 2012-07-06
    Description: Cytochrome c oxidase is a member of the haem copper oxidase superfamily (HCO). HCOs function as the terminal enzymes in the respiratory chain of mitochondria and aerobic prokaryotes, coupling molecular oxygen reduction to transmembrane proton pumping. Integral to the enzyme's function is the transfer of electrons from cytochrome c to the oxidase via a transient association of the two proteins. Electron entry and exit are proposed to occur from the same site on cytochrome c. Here we report the crystal structure of the caa3-type cytochrome oxidase from Thermus thermophilus, which has a covalently tethered cytochrome c domain. Crystals were grown in a bicontinuous mesophase using a synthetic short-chain monoacylglycerol as the hosting lipid. From the electron density map, at 2.36 A resolution, a novel integral membrane subunit and a native glycoglycerophospholipid embedded in the complex were identified. Contrary to previous electron transfer mechanisms observed for soluble cytochrome c, the structure reveals the architecture of the electron transfer complex for the fused cupredoxin/cytochrome c domain, which implicates different sites on cytochrome c for electron entry and exit. Support for an alternative to the classical proton gate characteristic of this HCO class is presented.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3428721/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3428721/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lyons, Joseph A -- Aragao, David -- Slattery, Orla -- Pisliakov, Andrei V -- Soulimane, Tewfik -- Caffrey, Martin -- GM75915/GM/NIGMS NIH HHS/ -- P50 GM073210/GM/NIGMS NIH HHS/ -- P50GM073210/GM/NIGMS NIH HHS/ -- R01 GM061070/GM/NIGMS NIH HHS/ -- R01 GM075915/GM/NIGMS NIH HHS/ -- U54 GM094599/GM/NIGMS NIH HHS/ -- U54GM094599/GM/NIGMS NIH HHS/ -- England -- Nature. 2012 Jul 26;487(7408):514-8. doi: 10.1038/nature11182.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Chemical and Environmental Sciences, University of Limerick, Limerick, Ireland.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22763450" target="_blank"〉PubMed〈/a〉
    Keywords: Azurin/metabolism ; Catalytic Domain ; Cell Membrane/metabolism ; Crystallization ; Crystallography, X-Ray ; Cytochrome c Group/*metabolism ; Cytochromes a/*metabolism ; Cytochromes a3/*metabolism ; Electron Transport ; Electron Transport Complex IV/*chemistry/*metabolism ; Electrons ; Glycerophospholipids/chemistry/metabolism ; Models, Molecular ; Oxygen/metabolism ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; Protons ; Thermus thermophilus/*enzymology ; Water/chemistry/metabolism
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  • 93
    Publication Date: 2012-03-13
    Description: Food-borne hemorrhagic Escherichia coli, exemplified by the strains O157:H7 and O104:H4 (refs 1, 2), require elaborate acid-resistance systems (ARs) to survive the extremely acidic environment such as the stomach (pH approximately 2). AR2 expels intracellular protons through the decarboxylation of L-glutamate (Glu) in the cytoplasm and exchange of the reaction product gamma-aminobutyric acid (GABA) with extracellular Glu. The latter process is mediated by the Glu-GABA antiporter GadC, a representative member of the amino-acid-polyamine-organocation superfamily of membrane transporters. The functional mechanism of GadC remains largely unknown. Here we show, with the use of an in vitro proteoliposome-based assay, that GadC transports GABA/Glu only under acidic conditions, with no detectable activity at pH values higher than 6.5. We determined the crystal structure of E. coli GadC at 3.1 A resolution under basic conditions. GadC, comprising 12 transmembrane segments (TMs), exists in a closed state, with its carboxy-terminal domain serving as a plug to block an otherwise inward-open conformation. Structural and biochemical analyses reveal the essential transport residues, identify the transport path and suggest a conserved transport mechanism involving the rigid-body rotation of a helical bundle for GadC and other amino acid antiporters.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ma, Dan -- Lu, Peilong -- Yan, Chuangye -- Fan, Chao -- Yin, Ping -- Wang, Jiawei -- Shi, Yigong -- England -- Nature. 2012 Mar 11;483(7391):632-6. doi: 10.1038/nature10917.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Ministry of Education Protein Science Laboratory, Center for Structural Biology, Tsinghua University, Beijing 100084, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22407317" target="_blank"〉PubMed〈/a〉
    Keywords: Antiporters/*chemistry/*metabolism ; Biological Transport ; Crystallography, X-Ray ; Escherichia coli O157/*chemistry ; Escherichia coli Proteins/*chemistry/*metabolism ; Glutamic Acid/*metabolism ; Membrane Proteins/*chemistry/*metabolism ; Models, Molecular ; Protein Structure, Tertiary ; Proteolipids/metabolism ; Rotation ; Structure-Activity Relationship ; gamma-Aminobutyric Acid/*metabolism
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  • 94
    Publication Date: 2012-05-19
    Description: The opioid receptor family comprises three members, the micro-, delta- and kappa-opioid receptors, which respond to classical opioid alkaloids such as morphine and heroin as well as to endogenous peptide ligands like endorphins. They belong to the G-protein-coupled receptor (GPCR) superfamily, and are excellent therapeutic targets for pain control. The delta-opioid receptor (delta-OR) has a role in analgesia, as well as in other neurological functions that remain poorly understood. The structures of the micro-OR and kappa-OR have recently been solved. Here we report the crystal structure of the mouse delta-OR, bound to the subtype-selective antagonist naltrindole. Together with the structures of the micro-OR and kappa-OR, the delta-OR structure provides insights into conserved elements of opioid ligand recognition while also revealing structural features associated with ligand-subtype selectivity. The binding pocket of opioid receptors can be divided into two distinct regions. Whereas the lower part of this pocket is highly conserved among opioid receptors, the upper part contains divergent residues that confer subtype selectivity. This provides a structural explanation and validation for the 'message-address' model of opioid receptor pharmacology, in which distinct 'message' (efficacy) and 'address' (selectivity) determinants are contained within a single ligand. Comparison of the address region of the delta-OR with other GPCRs reveals that this structural organization may be a more general phenomenon, extending to other GPCR families as well.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3523198/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3523198/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Granier, Sebastien -- Manglik, Aashish -- Kruse, Andrew C -- Kobilka, Tong Sun -- Thian, Foon Sun -- Weis, William I -- Kobilka, Brian K -- DA031418/DA/NIDA NIH HHS/ -- NS028471/NS/NINDS NIH HHS/ -- R01 GM083118/GM/NIGMS NIH HHS/ -- R01 NS028471/NS/NINDS NIH HHS/ -- R21 DA031418/DA/NIDA NIH HHS/ -- England -- Nature. 2012 May 16;485(7398):400-4. doi: 10.1038/nature11111.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, USA. granier@stanford.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22596164" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Binding Sites ; Conserved Sequence ; Crystallography, X-Ray ; Mice ; Models, Molecular ; Molecular Sequence Data ; Naltrexone/*analogs & derivatives/chemistry/metabolism/pharmacology ; Protein Structure, Tertiary ; Receptors, Opioid, delta/antagonists & inhibitors/*chemistry/metabolism ; Reproducibility of Results ; Structure-Activity Relationship ; Substrate Specificity
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  • 95
    Publication Date: 2012-11-16
    Description: The general transcription factor (TF) IIB is required for RNA polymerase (Pol) II initiation and extends with its B-reader element into the Pol II active centre cleft. Low-resolution structures of the Pol II-TFIIB complex indicated how TFIIB functions in DNA recruitment, but they lacked nucleic acids and half of the B-reader, leaving other TFIIB functions enigmatic. Here we report crystal structures of the Pol II-TFIIB complex from the yeast Saccharomyces cerevisiae at 3.4 A resolution and of an initially transcribing complex that additionally contains the DNA template and a 6-nucleotide RNA product. The structures reveal the entire B-reader and protein-nucleic acid interactions, and together with functional data lead to a more complete understanding of transcription initiation. TFIIB partially closes the polymerase cleft to position DNA and assist in its opening. The B-reader does not reach the active site but binds the DNA template strand upstream to assist in the recognition of the initiator sequence and in positioning the transcription start site. TFIIB rearranges active-site residues, induces binding of the catalytic metal ion B, and stimulates initial RNA synthesis allosterically. TFIIB then prevents the emerging DNA-RNA hybrid duplex from tilting, which would impair RNA synthesis. When the RNA grows beyond 6 nucleotides, it is separated from DNA and is directed to its exit tunnel by the B-reader loop. Once the RNA grows to 12-13 nucleotides, it clashes with TFIIB, triggering TFIIB displacement and elongation complex formation. Similar mechanisms may underlie all cellular transcription because all eukaryotic and archaeal RNA polymerases use TFIIB-like factors, and the bacterial initiation factor sigma has TFIIB-like topology and contains the loop region 3.2 that resembles the B-reader loop in location, charge and function. TFIIB and its counterparts may thus account for the two fundamental properties that distinguish RNA from DNA polymerases: primer-independent chain initiation and product separation from the template.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sainsbury, Sarah -- Niesser, Jurgen -- Cramer, Patrick -- England -- Nature. 2013 Jan 17;493(7432):437-40. doi: 10.1038/nature11715. Epub 2012 Nov 14.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Gene Center and Department of Biochemistry, Center for Integrated Protein Science CIPSM, Ludwig-Maximilians-Universitat Munchen, Feodor-Lynen-Str. 25, 81377 Munich, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23151482" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Biocatalysis ; Crystallography, X-Ray ; DNA/genetics/metabolism ; Models, Molecular ; Molecular Sequence Data ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; RNA Polymerase II/*chemistry/*metabolism ; RNA, Messenger/biosynthesis/metabolism ; Saccharomyces cerevisiae/enzymology ; Structure-Activity Relationship ; Templates, Genetic ; Transcription Factor TFIIB/*chemistry/*metabolism ; *Transcription Initiation, Genetic
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  • 96
    Publication Date: 2012-12-14
    Description: Long-term potentiation (LTP) of synaptic transmission is thought to be an important cellular mechanism underlying memory formation. A widely accepted model posits that LTP requires the cytoplasmic carboxyl tail (C-tail) of the AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptor subunit GluA1. To find the minimum necessary requirement of the GluA1 C-tail for LTP in mouse CA1 hippocampal pyramidal neurons, we used a single-cell molecular replacement strategy to replace all endogenous AMPA receptors with transfected subunits. In contrast to the prevailing model, we found no requirement of the GluA1 C-tail for LTP. In fact, replacement with the GluA2 subunit showed normal LTP, as did an artificially expressed kainate receptor not normally found at these synapses. The only conditions under which LTP was impaired were those with markedly decreased AMPA receptor surface expression, indicating a requirement for a reserve pool of receptors. These results demonstrate the synapse's remarkable flexibility to potentiate with a variety of glutamate receptor subtypes, requiring a fundamental change in our thinking with regard to the core molecular events underlying synaptic plasticity.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3998843/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3998843/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Granger, Adam J -- Shi, Yun -- Lu, Wei -- Cerpas, Manuel -- Nicoll, Roger A -- R01 MH070957/MH/NIMH NIH HHS/ -- England -- Nature. 2013 Jan 24;493(7433):495-500. doi: 10.1038/nature11775. Epub 2012 Dec 12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Neuroscience Graduate Program, University of California San Francisco, California 94158, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23235828" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Gene Deletion ; Long-Term Potentiation/*physiology ; Mice ; Models, Neurological ; Protein Structure, Tertiary ; Protein Subunits/*metabolism ; Protein Transport ; Receptors, AMPA/chemistry/deficiency/genetics/metabolism ; Receptors, Ionotropic Glutamate/*chemistry/*metabolism ; Receptors, Kainic Acid/metabolism ; Synapses/metabolism ; Synaptic Transmission
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  • 97
    Publication Date: 2012-01-24
    Description: Fic proteins that are defined by the ubiquitous FIC (filamentation induced by cyclic AMP) domain are known to catalyse adenylylation (also called AMPylation); that is, the transfer of AMP onto a target protein. In mammalian cells, adenylylation of small GTPases through Fic proteins injected by pathogenic bacteria can cause collapse of the actin cytoskeleton and cell death. It is unknown how this potentially deleterious adenylylation activity is regulated in the widespread Fic proteins that are found in all domains of life and that are thought to have critical roles in intrinsic signalling processes. Here we show that FIC-domain-mediated adenylylation is controlled by a conserved mechanism of ATP-binding-site obstruction that involves an inhibitory alpha-helix (alpha(inh)) with a conserved (S/T)XXXE(G/N) motif, and that in this mechanism the invariable glutamate competes with ATP gamma-phosphate binding. Consistent with this, FIC-domain-mediated growth arrest of bacteria by the VbhT toxin of Bartonella schoenbuchensis is intermolecularly repressed by the VbhA antitoxin through tight binding of its alpha(inh) to the FIC domain of VbhT, as shown by structure and function analysis. Furthermore, structural comparisons with other bacterial Fic proteins, such as Fic of Neisseria meningitidis and of Shewanella oneidensis, show that alpha(inh) frequently constitutes an amino-terminal or carboxy-terminal extension to the FIC domain, respectively, partially obstructing the ATP binding site in an intramolecular manner. After mutation of the inhibitory motif in various Fic proteins, including the human homologue FICD (also known as HYPE), adenylylation activity is considerably boosted, consistent with the anticipated relief of inhibition. Structural homology modelling of all annotated Fic proteins indicates that inhibition by alpha(inh) is universal and conserved through evolution, as the inhibitory motif is present in approximately 90% of all putatively adenylylation-active FIC domains, including examples from all domains of life and from viruses. Future studies should reveal how intrinsic or extrinsic factors modulate adenylylation activity by weakening the interaction of alpha(inh) with the FIC active site.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Engel, Philipp -- Goepfert, Arnaud -- Stanger, Frederic V -- Harms, Alexander -- Schmidt, Alexander -- Schirmer, Tilman -- Dehio, Christoph -- England -- Nature. 2012 Jan 22;482(7383):107-10. doi: 10.1038/nature10729.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Focal Area Infection Biology, Biozentrum, University of Basel, CH-4056 Basel, Switzerland.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22266942" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Amino Acid Sequence ; Bacterial Proteins/*chemistry/*metabolism ; Bartonella ; Carrier Proteins/chemistry/metabolism ; Catalysis ; Catalytic Domain ; Cyclic AMP/*metabolism ; Escherichia coli ; Escherichia coli Proteins/chemistry/metabolism ; Glutamic Acid/metabolism ; Humans ; Membrane Proteins/chemistry/metabolism ; Microbial Viability ; Models, Molecular ; Molecular Weight ; Neisseria meningitidis ; Protein Structure, Tertiary ; Shewanella
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  • 98
    Publication Date: 2012-11-09
    Description: Unlike random heteropolymers, natural proteins fold into unique ordered structures. Understanding how these are encoded in amino-acid sequences is complicated by energetically unfavourable non-ideal features--for example kinked alpha-helices, bulged beta-strands, strained loops and buried polar groups--that arise in proteins from evolutionary selection for biological function or from neutral drift. Here we describe an approach to designing ideal protein structures stabilized by completely consistent local and non-local interactions. The approach is based on a set of rules relating secondary structure patterns to protein tertiary motifs, which make possible the design of funnel-shaped protein folding energy landscapes leading into the target folded state. Guided by these rules, we designed sequences predicted to fold into ideal protein structures consisting of alpha-helices, beta-strands and minimal loops. Designs for five different topologies were found to be monomeric and very stable and to adopt structures in solution nearly identical to the computational models. These results illuminate how the folding funnels of natural proteins arise and provide the foundation for engineering a new generation of functional proteins free from natural evolution.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3705962/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3705962/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Koga, Nobuyasu -- Tatsumi-Koga, Rie -- Liu, Gaohua -- Xiao, Rong -- Acton, Thomas B -- Montelione, Gaetano T -- Baker, David -- U54 GM094597/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2012 Nov 8;491(7423):222-7. doi: 10.1038/nature11600.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉University of Washington, Department of Biochemistry and Howard Hughes Medical Institute, Seattle, Washington 98195, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23135467" target="_blank"〉PubMed〈/a〉
    Keywords: *Computer Simulation ; *Models, Molecular ; *Protein Folding ; *Protein Stability ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Proteins/*chemistry ; Thermodynamics
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  • 99
    Publication Date: 2012-03-09
    Description: Dyneins are microtubule-based AAA(+) motor complexes that power ciliary beating, cell division, cell migration and intracellular transport. Here we report the most complete structure obtained so far, to our knowledge, of the 380-kDa motor domain of Dictyostelium discoideum cytoplasmic dynein at 2.8 A resolution; the data are reliable enough to discuss the structure and mechanism at the level of individual amino acid residues. Features that can be clearly visualized at this resolution include the coordination of ADP in each of four distinct nucleotide-binding sites in the ring-shaped AAA(+) ATPase unit, a newly identified interaction interface between the ring and mechanical linker, and junctional structures between the ring and microtubule-binding stalk, all of which should be critical for the mechanism of dynein motility. We also identify a long-range allosteric communication pathway between the primary ATPase and the microtubule-binding sites. Our work provides a framework for understanding the mechanism of dynein-based motility.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kon, Takahide -- Oyama, Takuji -- Shimo-Kon, Rieko -- Imamula, Kenji -- Shima, Tomohiro -- Sutoh, Kazuo -- Kurisu, Genji -- England -- Nature. 2012 Mar 7;484(7394):345-50. doi: 10.1038/nature10955.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan. takahide.kon@protein.osaka-u.ac.jp〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22398446" target="_blank"〉PubMed〈/a〉
    Keywords: Adenosine Diphosphate/metabolism ; Adenosine Triphosphate/metabolism ; Allosteric Regulation ; Binding Sites ; Crystallography, X-Ray ; Cytoplasmic Dyneins/*chemistry/metabolism ; Dictyostelium/*chemistry ; Hydrolysis ; Microtubules/metabolism ; Models, Biological ; Models, Molecular ; Movement ; Protein Structure, Tertiary ; Structure-Activity Relationship
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  • 100
    Publication Date: 2012-03-03
    Description: Ubiquitin (Ub) and ubiquitin-like (Ubl) modifiers such as SUMO (also known as Smt3 in Saccharomyces cerevisiae) mediate signal transduction through post-translational modification of substrate proteins in pathways that control differentiation, apoptosis and the cell cycle, and responses to stress such as the DNA damage response. In yeast, the proliferating cell nuclear antigen PCNA (also known as Pol30) is modified by ubiquitin in response to DNA damage and by SUMO during S phase. Whereas Ub-PCNA can signal for recruitment of translesion DNA polymerases, SUMO-PCNA signals for recruitment of the anti-recombinogenic DNA helicase Srs2. It remains unclear how receptors such as Srs2 specifically recognize substrates after conjugation to Ub and Ubls. Here we show, through structural, biochemical and functional studies, that the Srs2 carboxy-terminal domain harbours tandem receptor motifs that interact independently with PCNA and SUMO and that both motifs are required to recognize SUMO-PCNA specifically. The mechanism presented is pertinent to understanding how other receptors specifically recognize Ub- and Ubl-modified substrates to facilitate signal transduction.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3306252/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3306252/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Armstrong, Anthony A -- Mohideen, Firaz -- Lima, Christopher D -- F32 GM086066/GM/NIGMS NIH HHS/ -- F32 GM086066-01/GM/NIGMS NIH HHS/ -- F32 GM086066-02/GM/NIGMS NIH HHS/ -- P30 EB009998/EB/NIBIB NIH HHS/ -- P41RR012408/RR/NCRR NIH HHS/ -- R01 GM065872/GM/NIGMS NIH HHS/ -- R01 GM065872-08/GM/NIGMS NIH HHS/ -- R01 GM065872-09/GM/NIGMS NIH HHS/ -- R01 GM065872-10/GM/NIGMS NIH HHS/ -- R01 GM065872-11/GM/NIGMS NIH HHS/ -- R01 GM065872-12/GM/NIGMS NIH HHS/ -- RR-15301/RR/NCRR NIH HHS/ -- England -- Nature. 2012 Feb 29;483(7387):59-63. doi: 10.1038/nature10883.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Structural Biology Program, Sloan-Kettering Institute, New York, New York 10065, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22382979" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Antigens, Nuclear/*chemistry/*metabolism ; Binding Sites ; Crystallography, X-Ray ; DNA Helicases/*chemistry/*metabolism ; Methylation ; Models, Molecular ; Proliferating Cell Nuclear Antigen/chemistry/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Saccharomyces cerevisiae/*chemistry/genetics/growth & development ; Saccharomyces cerevisiae Proteins/*chemistry/*metabolism ; Small Ubiquitin-Related Modifier Proteins/chemistry/*metabolism ; Structure-Activity Relationship ; *Sumoylation
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