ALBERT

Description: G-protein-coupled receptors (GPCRs) comprise the largest family of membrane proteins in the human genome and mediate cellular responses to an extensive array of hormones, neurotransmitters and sensory stimuli. Although some crystal structures have been determined for GPCRs, most are for modified forms, showing little basal activity, and are bound to inverse agonists or antagonists. Consequently, these structures correspond to receptors in their inactive states. The visual pigment rhodopsin is the only GPCR for which structures exist that are thought to be in the active state. However, these structures are for the apoprotein, or opsin, form that does not contain the agonist all-trans retinal. Here we present a crystal structure at a resolution of 3 A for the constitutively active rhodopsin mutant Glu 113 Gln in complex with a peptide derived from the carboxy terminus of the alpha-subunit of the G protein transducin. The protein is in an active conformation that retains retinal in the binding pocket after photoactivation. Comparison with the structure of ground-state rhodopsin suggests how translocation of the retinal beta-ionone ring leads to a rotation of transmembrane helix 6, which is the critical conformational change on activation. A key feature of this conformational change is a reorganization of water-mediated hydrogen-bond networks between the retinal-binding pocket and three of the most conserved GPCR sequence motifs. We thus show how an agonist ligand can activate its GPCR.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3715716/" 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/PMC3715716/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Standfuss, Jorg -- Edwards, Patricia C -- D'Antona, Aaron -- Fransen, Maikel -- Xie, Guifu -- Oprian, Daniel D -- Schertler, Gebhard F X -- EY007965/EY/NEI NIH HHS/ -- MC_U105178937/Medical Research Council/United Kingdom -- MC_U105197215/Medical Research Council/United Kingdom -- R01 EY007965/EY/NEI NIH HHS/ -- England -- Nature. 2011 Mar 31;471(7340):656-60. doi: 10.1038/nature09795. Epub 2011 Mar 9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Paul Scherrer Institut, 5232 Villigen PSI, Switzerland.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21389983" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Standfuss, Jorg -- New York, N.Y. -- Science. 2015 Mar 6;347(6226):1071-2. doi: 10.1126/science.aaa7998.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Biomolecular Research, Paul Scherrer Institute, Villigen PSI, 5232 Switzerland. joerg.standfuss@psi.ch.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25745149" target="_blank"〉PubMed〈/a〉

Description: G-protein-coupled receptors (GPCRs) signal primarily through G proteins or arrestins. Arrestin binding to GPCRs blocks G protein interaction and redirects signalling to numerous G-protein-independent pathways. Here we report the crystal structure of a constitutively active form of human rhodopsin bound to a pre-activated form of the mouse visual arrestin, determined by serial femtosecond X-ray laser crystallography. Together with extensive biochemical and mutagenesis data, the structure reveals an overall architecture of the rhodopsin-arrestin assembly in which rhodopsin uses distinct structural elements, including transmembrane helix 7 and helix 8, to recruit arrestin. Correspondingly, arrestin adopts the pre-activated conformation, with a approximately 20 degrees rotation between the amino and carboxy domains, which opens up a cleft in arrestin to accommodate a short helix formed by the second intracellular loop of rhodopsin. This structure provides a basis for understanding GPCR-mediated arrestin-biased signalling and demonstrates the power of X-ray lasers for advancing the frontiers of structural biology.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4521999/" 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/PMC4521999/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kang, Yanyong -- Zhou, X Edward -- Gao, Xiang -- He, Yuanzheng -- Liu, Wei -- Ishchenko, Andrii -- Barty, Anton -- White, Thomas A -- Yefanov, Oleksandr -- Han, Gye Won -- Xu, Qingping -- de Waal, Parker W -- Ke, Jiyuan -- Tan, M H Eileen -- Zhang, Chenghai -- Moeller, Arne -- West, Graham M -- Pascal, Bruce D -- Van Eps, Ned -- Caro, Lydia N -- Vishnivetskiy, Sergey A -- Lee, Regina J -- Suino-Powell, Kelly M -- Gu, Xin -- Pal, Kuntal -- Ma, Jinming -- Zhi, Xiaoyong -- Boutet, Sebastien -- Williams, Garth J -- Messerschmidt, Marc -- Gati, Cornelius -- Zatsepin, Nadia A -- Wang, Dingjie -- James, Daniel -- Basu, Shibom -- Roy-Chowdhury, Shatabdi -- Conrad, Chelsie E -- Coe, Jesse -- Liu, Haiguang -- Lisova, Stella -- Kupitz, Christopher -- Grotjohann, Ingo -- Fromme, Raimund -- Jiang, Yi -- Tan, Minjia -- Yang, Huaiyu -- Li, Jun -- Wang, Meitian -- Zheng, Zhong -- Li, Dianfan -- Howe, Nicole -- Zhao, Yingming -- Standfuss, Jorg -- Diederichs, Kay -- Dong, Yuhui -- Potter, Clinton S -- Carragher, Bridget -- Caffrey, Martin -- Jiang, Hualiang -- Chapman, Henry N -- Spence, John C H -- Fromme, Petra -- Weierstall, Uwe -- Ernst, Oliver P -- Katritch, Vsevolod -- Gurevich, Vsevolod V -- Griffin, Patrick R -- Hubbell, Wayne L -- Stevens, Raymond C -- Cherezov, Vadim -- Melcher, Karsten -- Xu, H Eric -- DK071662/DK/NIDDK NIH HHS/ -- EY005216/EY/NEI NIH HHS/ -- EY011500/EY/NEI NIH HHS/ -- GM073197/GM/NIGMS NIH HHS/ -- GM077561/GM/NIGMS NIH HHS/ -- GM095583/GM/NIGMS NIH HHS/ -- GM097463/GM/NIGMS NIH HHS/ -- GM102545/GM/NIGMS NIH HHS/ -- GM103310/GM/NIGMS NIH HHS/ -- GM104212/GM/NIGMS NIH HHS/ -- GM108635/GM/NIGMS NIH HHS/ -- P30EY000331/EY/NEI NIH HHS/ -- P41 GM103310/GM/NIGMS NIH HHS/ -- P41GM103393/GM/NIGMS NIH HHS/ -- P41RR001209/RR/NCRR NIH HHS/ -- P50 GM073197/GM/NIGMS NIH HHS/ -- P50 GM073210/GM/NIGMS NIH HHS/ -- R01 DK066202/DK/NIDDK NIH HHS/ -- R01 DK071662/DK/NIDDK NIH HHS/ -- R01 EY011500/EY/NEI NIH HHS/ -- R01 GM087413/GM/NIGMS NIH HHS/ -- R01 GM109955/GM/NIGMS NIH HHS/ -- S10 RR027270/RR/NCRR NIH HHS/ -- U54 GM094586/GM/NIGMS NIH HHS/ -- U54 GM094599/GM/NIGMS NIH HHS/ -- U54 GM094618/GM/NIGMS NIH HHS/ -- England -- Nature. 2015 Jul 30;523(7562):561-7. doi: 10.1038/nature14656. Epub 2015 Jul 22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Structural Sciences, Center for Structural Biology and Drug Discovery, Van Andel Research Institute, Grand Rapids, Michigan 49503, USA. ; Department of Chemistry and Biochemistry, and Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, Arizona 85287-1604, USA. ; Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, California 90089, USA. ; Center for Free Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany. ; Joint Center for Structural Genomics, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA. ; 1] Laboratory of Structural Sciences, Center for Structural Biology and Drug Discovery, Van Andel Research Institute, Grand Rapids, Michigan 49503, USA [2] Department of Obstetrics &Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore. ; The National Resource for Automated Molecular Microscopy, New York Structural Biology Center, New York, New York 10027, USA. ; Department of Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458, USA. ; Jules Stein Eye Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA. ; Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada. ; Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, USA. ; Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA. ; 1] Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] BioXFEL, NSF Science and Technology Center, 700 Ellicott Street, Buffalo, New York 14203, USA. ; 1] Department of Chemistry and Biochemistry, and Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, Arizona 85287-1604, USA [2] Department of Physics, Arizona State University, Tempe, Arizona 85287, USA. ; 1] Department of Chemistry and Biochemistry, and Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, Arizona 85287-1604, USA [2] Beijing Computational Science Research Center, Haidian District, Beijing 10084, China. ; 1] Department of Chemistry and Biochemistry, and Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, Arizona 85287-1604, USA [2] Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA. ; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China. ; Department of Obstetrics &Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore. ; Swiss Light Source at Paul Scherrer Institute, CH-5232 Villigen, Switzerland. ; Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, California 90089, USA. ; School of Medicine and School of Biochemistry and Immunology, Trinity College, Dublin 2, Ireland. ; 1] BioXFEL, NSF Science and Technology Center, 700 Ellicott Street, Buffalo, New York 14203, USA [2] Ben May Department for Cancer Research, University of Chicago, Chicago, Illinois 60637, USA. ; Laboratory of Biomolecular Research at Paul Scherrer Institute, CH-5232 Villigen, Switzerland. ; Department of Biology, Universitat Konstanz, 78457 Konstanz, Germany. ; Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China. ; 1] Center for Free Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany [2] Centre for Ultrafast Imaging, 22761 Hamburg, Germany. ; 1] Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada [2] Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada. ; 1] Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, California 90089, USA [2] Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, California 90089, USA [3] iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China. ; 1] Laboratory of Structural Sciences, Center for Structural Biology and Drug Discovery, Van Andel Research Institute, Grand Rapids, Michigan 49503, USA [2] VARI-SIMM Center, Center for Structure and Function of Drug Targets, CAS-Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26200343" target="_blank"〉PubMed〈/a〉

Description: 〈p〉Conformational dynamics are essential for proteins to function. We adapted time-resolved serial crystallography developed at x-ray lasers to visualize protein motions using synchrotrons. We recorded the structural changes in the light-driven proton-pump bacteriorhodopsin over 200 milliseconds in time. The snapshot from the first 5 milliseconds after photoactivation shows structural changes associated with proton release at a quality comparable to that of previous x-ray laser experiments. From 10 to 15 milliseconds onwards, we observe large additional structural rearrangements up to 9 angstroms on the cytoplasmic side. Rotation of leucine-93 and phenylalanine-219 opens a hydrophobic barrier, leading to the formation of a water chain connecting the intracellular aspartic acid–96 with the retinal Schiff base. The formation of this proton wire recharges the membrane pump with a proton for the next cycle.〈/p〉

Description: G protein-coupled receptors (GPCR) are seven transmembrane helix proteins that couple binding of extracellular ligands to conformational changes and activation of intracellular G proteins, GPCR kinases, and arrestins. Constitutively active mutants are ubiquitously found among GPCRs and increase the inherent basal activity of the receptor, which often correlates with a pathological outcome. Here, we have used the M257Y6.40 constitutively active mutant of the photoreceptor rhodopsin in combination with the specific binding of a C-terminal fragment from the G protein alpha subunit (GαCT) to trap a light activated state for crystallization. The structure of the M257Y/GαCT complex contains the agonist all-trans-retinal covalently bound to the native binding pocket and resembles the G protein binding metarhodopsin-II conformation obtained by the natural activation mechanism; i.e., illumination of the prebound chromophore 11-cis-retinal. The structure further suggests a molecular basis for the constitutive activity of 6.40 substitutions and the strong effect of the introduced tyrosine based on specific interactions with Y2235.58 in helix 5, Y3067.53 of the NPxxY motif and R1353.50 of the E(D)RY motif, highly conserved residues of the G protein binding site.

Description: Selective coupling of G protein (heterotrimeric guanine nucleotide–binding protein)–coupled receptors (GPCRs) to specific Gα-protein subtypes is critical to transform extracellular signals, carried by natural ligands and clinical drugs, into cellular responses. At the center of this transduction event lies the formation of a signaling complex between the receptor and G protein. We report the crystal structure of light-sensitive GPCR rhodopsin bound to an engineered mini-G o protein. The conformation of the receptor is identical to all previous structures of active rhodopsin, including the complex with arrestin. Thus, rhodopsin seems to adopt predominantly one thermodynamically stable active conformation, effectively acting like a "structural switch," allowing for maximum efficiency in the visual system. Furthermore, our analysis of the well-defined GPCR–G protein interface suggests that the precise position of the carboxyl-terminal "hook-like" element of the G protein (its four last residues) relative to the TM7/helix 8 (H8) joint of the receptor is a significant determinant in selective G protein activation.

Description: Ultrafast isomerization of retinal is the primary step in photoresponsive biological functions including vision in humans and ion transport across bacterial membranes. We used an x-ray laser to study the subpicosecond structural dynamics of retinal isomerization in the light-driven proton pump bacteriorhodopsin. A series of structural snapshots with near-atomic spatial resolution and temporal resolution in the femtosecond regime show how the excited all-trans retinal samples conformational states within the protein binding pocket before passing through a twisted geometry and emerging in the 13-cis conformation. Our findings suggest ultrafast collective motions of aspartic acid residues and functional water molecules in the proximity of the retinal Schiff base as a key facet of this stereoselective and efficient photochemical reaction.

Description: Arrestins function as adapter proteins that mediate G protein-coupled receptor (GPCR) desensitization, internalization, and additional rounds of signaling. Here we have compared binding of the GPCR rhodopsin to 403 mutants of arrestin-1 covering its complete sequence. This comprehensive and unbiased mutagenesis approach provides a functional dimension to the crystal structures...