ALBERT

Description: Crystal structures of 5-aminoimidazole ribonucleotide (AIR) synthetase, also known as PurM, from Thermus thermophilus ( Tt ) and Geobacillus kaustophilus ( Gk ) were determined. For Tt PurM, the maximum resolution was 2.2 Å and the space group was P 2 1 2 1 2 with four dimers in an asymmetric unit. For Gk PurM, the maximum resolution was 2.2 Å and the space group was P 2 1 2 1 2 with one monomer in asymmetric unit. The biological unit is dimer for both Tt PurM and Gk PurM and the dimer structures were similar to previously determined structures of PurM in general. For Tt PurM, ~50 residues at the amino terminal were disordered in the crystal structure whereas, for Gk PurM, the corresponding region covered the ATP-binding site forming an α helix in part, suggesting that the N-terminal region of PurM changes its conformation upon binding of ligands. FGAM binding site was predicted by the docking simulation followed by the MD simulation based on the SO 4 2– binding site found in the crystal structure of Tt PurM.

Description: In the Vietnamese Mekong Delta (VMD), water levels at some stations have increased. However, the factors that cause this rise in the VMD have not been identified. We considered four factors that may have contributed to the water level rise: (1) increased runoff from upstream, (2) sea-level rise, (3) land subsidence, and (4) decrease in flood mitigation function due to construction of high dykes. We analyzed daily maximum and minimum water levels, and mean daily water levels from 24 monitoring stations from 1987 to 2006. Using daily and annual water level differences, we classified the delta into two groups; one is dominated by flows from upstream, while the other is tide-dominated. We then tested the trends of annual maximum and minimum water levels using the Mann-Kendall test, and identified the slope of the trend using the method of Sen. The areas of dyke construction were estimated using the Enhanced Vegetation Index (EVI) and Land Surface Water Index (LSWI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) data. Results show (1) river inflow has little impact on rising water levels in the VMD, (2) the influence of high dykes on water level rise could not be quantified in this study, (3) both maximum and minimum water levels significantly increased in the tide-dominated area. Trend of annual minimum water level can be considered as the sum sea-level rise and land subsidence. Therefore, we attribute 6.05 mm year −1 (80%) to land subsidence and 1.42 mm year −1 (20%) to sea level rise, indicating inundations have been severe in the VMD, caused primarily by land subsidence. This article is protected by copyright. All rights reserved.

Description: Adiponectin stimulation of its receptors, AdipoR1 and AdipoR2, increases the activities of 5' AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor (PPAR), respectively, thereby contributing to healthy longevity as key anti-diabetic molecules. AdipoR1 and AdipoR2 were predicted to contain seven transmembrane helices with the opposite topology to G-protein-coupled receptors. Here we report the crystal structures of human AdipoR1 and AdipoR2 at 2.9 and 2.4 A resolution, respectively, which represent a novel class of receptor structure. The seven-transmembrane helices, conformationally distinct from those of G-protein-coupled receptors, enclose a large cavity where three conserved histidine residues coordinate a zinc ion. The zinc-binding structure may have a role in the adiponectin-stimulated AMPK phosphorylation and UCP2 upregulation. Adiponectin may broadly interact with the extracellular face, rather than the carboxy-terminal tail, of the receptors. The present information will facilitate the understanding of novel structure-function relationships and the development and optimization of AdipoR agonists for the treatment of obesity-related diseases, such as type 2 diabetes.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4477036/" 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/PMC4477036/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Tanabe, Hiroaki -- Fujii, Yoshifumi -- Okada-Iwabu, Miki -- Iwabu, Masato -- Nakamura, Yoshihiro -- Hosaka, Toshiaki -- Motoyama, Kanna -- Ikeda, Mariko -- Wakiyama, Motoaki -- Terada, Takaho -- Ohsawa, Noboru -- Hato, Masakatsu -- Ogasawara, Satoshi -- Hino, Tomoya -- Murata, Takeshi -- Iwata, So -- Hirata, Kunio -- Kawano, Yoshiaki -- Yamamoto, Masaki -- Kimura-Someya, Tomomi -- Shirouzu, Mikako -- Yamauchi, Toshimasa -- Kadowaki, Takashi -- Yokoyama, Shigeyuki -- 062164/Z/00/Z/Wellcome Trust/United Kingdom -- 089809/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 -- England -- Nature. 2015 Apr 16;520(7547):312-6. doi: 10.1038/nature14301. Epub 2015 Apr 8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] Department of Biophysics and Biochemistry and Laboratory of Structural Biology, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan [3] Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [4] RIKEN Structural Biology Laboratory, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. ; 1] RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] RIKEN Structural Biology Laboratory, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. ; 1] Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan [2] Department of Integrated Molecular Science on Metabolic Diseases, 22nd Century Medical and Research Center, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. ; 1] Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan [2] Department of Integrated Molecular Science on Metabolic Diseases, 22nd Century Medical and Research Center, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan [3] PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan. ; 1] RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [3] RIKEN Structural Biology Laboratory, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. ; 1] RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. ; RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. ; Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan. ; 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. ; 1] RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan [3] JST, Research Acceleration Program, Membrane Protein Crystallography Project, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan [4] Department of Chemistry, Graduate School of Science, Chiba University, Yayoi-cho, Inage, Chiba 263-8522, Japan. ; 1] RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan [3] JST, Research Acceleration Program, Membrane Protein Crystallography Project, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan [4] Division of Molecular Biosciences, Membrane Protein Crystallography Group, Imperial College, London SW7 2AZ, UK [5] Diamond Light Source, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE, UK [6] RIKEN SPring-8 Center, Harima Institute, Kouto, Sayo, Hyogo 679-5148, Japan. ; RIKEN SPring-8 Center, Harima Institute, Kouto, Sayo, Hyogo 679-5148, Japan. ; 1] Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan [2] Department of Integrated Molecular Science on Metabolic Diseases, 22nd Century Medical and Research Center, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan [3] CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan. ; 1] RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] Department of Biophysics and Biochemistry and Laboratory of Structural Biology, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan [3] RIKEN Structural Biology Laboratory, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25855295" target="_blank"〉PubMed〈/a〉

Description: Eukaryotic cells restrict protein synthesis under various stress conditions, by inhibiting the eukaryotic translation initiation factor 2B (eIF2B). eIF2B is the guanine nucleotide exchange factor for eIF2, a heterotrimeric G protein consisting of alpha-, beta- and gamma-subunits. eIF2B exchanges GDP for GTP on the gamma-subunit of eIF2 (eIF2gamma), and is inhibited by stress-induced phosphorylation of eIF2alpha. eIF2B is a heterodecameric complex of two copies each of the alpha-, beta-, gamma-, delta- and epsilon-subunits; its alpha-, beta- and delta-subunits constitute the regulatory subcomplex, while the gamma- and epsilon-subunits form the catalytic subcomplex. The three-dimensional structure of the entire eIF2B complex has not been determined. Here we present the crystal structure of Schizosaccharomyces pombe eIF2B with an unprecedented subunit arrangement, in which the alpha2beta2delta2 hexameric regulatory subcomplex binds two gammaepsilon dimeric catalytic subcomplexes on its opposite sides. A structure-based in vitro analysis by a surface-scanning site-directed photo-cross-linking method identified the eIF2alpha-binding and eIF2gamma-binding interfaces, located far apart on the regulatory and catalytic subcomplexes, respectively. The eIF2gamma-binding interface is located close to the conserved 'NF motif', which is important for nucleotide exchange. A structural model was constructed for the complex of eIF2B with phosphorylated eIF2alpha, which binds to eIF2B more strongly than the unphosphorylated form. These results indicate that the eIF2alpha phosphorylation generates the 'nonproductive' eIF2-eIF2B complex, which prevents nucleotide exchange on eIF2gamma, and thus provide a structural framework for the eIF2B-mediated mechanism of stress-induced translational control.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kashiwagi, Kazuhiro -- Takahashi, Mari -- Nishimoto, Madoka -- Hiyama, Takuya B -- Higo, Toshiaki -- Umehara, Takashi -- Sakamoto, Kensaku -- Ito, Takuhiro -- Yokoyama, Shigeyuki -- England -- Nature. 2016 Mar 3;531(7592):122-5. doi: 10.1038/nature16991. Epub 2016 Feb 22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan. ; RIKEN Systems and Structural Biology Center, Tsurumi-ku, Yokohama 230-0045, Japan. ; RIKEN Center for Life Science Technologies, Tsurumi-ku, Yokohama 230-0045, Japan. ; RIKEN Structural Biology Laboratory, Tsurumi-ku, Yokohama 230-0045, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26901872" target="_blank"〉PubMed〈/a〉

Description: The deep trefoil knot architecture is unique to the SpoU and tRNA methyltransferase D (TrmD) (SPOUT) family of methyltransferases (MTases) in all three domains of life. In bacteria, TrmD catalyzes the N1-methylguanosine (m1G) modification at position 37 in transfer RNAs (tRNAs) with the 36GG37 sequence, using S-adenosyl-l-methionine (AdoMet) as the...

Description: Ultraviolet (UV) reception is useful for such basic behaviors as mate choice, foraging, predator avoidance, communication, and navigation, whereas violet reception improves visual resolution and subtle contrast detection. UV and violet reception are mediated by the short wavelength–sensitive (SWS1) pigments that absorb light maximally ( max ) at ~360 nm and ~395 to 440 nm, respectively. Because of strong nonadditive (epistatic) interactions among amino acid changes in the pigments, the adaptive evolutionary mechanisms of these phenotypes are not well understood. Evolution of the violet pigment of the African clawed frog ( Xenopus laevis , max = 423 nm) from the UV pigment in the amphibian ancestor ( max = 359 nm) can be fully explained by eight mutations in transmembrane (TM) I–III segments. We show that epistatic interactions involving the remaining TM IV–VII segments provided evolutionary potential for the frog pigment to gradually achieve its violet-light reception by tuning its color sensitivity in small steps. Mutants in these segments also impair pigments that would cause drastic spectral shifts and thus eliminate them from viable evolutionary pathways. The overall effects of epistatic interactions involving TM IV–VII segments have disappeared at the last evolutionary step and thus are not detectable by studying present-day pigments. Therefore, characterizing the genotype-phenotype relationship during each evolutionary step is the key to uncover the true nature of epistasis.

Description: Redshifted 21 cm signal is a promising tool to investigate the state of intergalactic medium (IGM) in the cosmic dawn (CD) and epoch of reionization (EoR). In our previous work, we studied the variance and skewness of the 21 cm fluctuations to give a clear interpretation of the 21 cm power spectrum and found that skewness is a good indicator of the epoch when X-ray heating becomes effective. Thus, the non-Gaussian feature of the spatial distribution of the 21 cm signal is expected to be useful to investigate the astrophysical effects in the CD and EoR. In this paper, in order to investigate such a non-Gaussian feature in more detail, we focus on the bispectrum of the 21 cm signal. It is expected that the 21 cm brightness temperature bispectrum is produced by non-Gaussianity due to the various astrophysical effects such as the Wouthuysen–Field effect, X-ray heating and reionization. We study the various properties of 21 cm bispectrum such as scale dependence, shape dependence and redshift evolution. And also we study the contribution from each component of 21 cm bispectrum. We find that the contribution from each component has characteristic scale-dependent feature. In particular, we find that the bulk of the 21 cm bispectrum at z = 20 comes from the matter fluctuations, while in other epochs it is mainly determined by the spin and/or neutral fraction fluctuations and it is expected that we could obtain more detailed information on the IGM in the CD and EoR by using the 21 cm bispectrum in the future experiments, combined with the power spectrum and skewness.

Description: 〈p〉Entanglement is the key resource for measurement-based quantum computing. It is stored in quantum states known as cluster states, which are prepared offline and enable quantum computing by means of purely local measurements. Universal quantum computing requires cluster states that are both large and possess (at least) a two-dimensional topology. Continuous-variable cluster states—based on bosonic modes rather than qubits—have previously been generated on a scale exceeding one million modes, but only in one dimension. Here, we report generation of a large-scale two-dimensional continuous-variable cluster state. Its structure consists of a 5- by 1240-site square lattice that was tailored to our highly scalable time-multiplexed experimental platform. It is compatible with Bosonic error-correcting codes that, with higher squeezing, enable fault-tolerant quantum computation.〈/p〉

Description: The redshifted 21cm line signal from neutral hydrogens is a promising tool to probe the cosmic dawn and the epoch of reionization. Ongoing and future low-frequency radio experiments are expected to detect its fluctuations, especially through the power spectrum. In this paper, we give a physical interpretation of the time evolution of the power spectrum of the 21cm brightness temperature fluctuations, which can be decomposed into dark matter density, spin temperature and neutral fraction of hydrogen fluctuations. From the one-point statistics of the fluctuations, such as variance and skewness, we find that the peaks and dips in the time evolution are deeply related to X-ray heating of the intergalactic gas, which controls the spin temperature. We suggest the skewness of the brightness temperature distribution is a key observable to identify the onset of X-ray heating.

Description: The mammalian lung is an elaborate branching organ, and it forms following a highly stereotypical morphogenesis program. It is well established that precise control at the transcript level is a key genetic underpinning of lung branching. In comparison, little is known about how regulation at the protein level may play...