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51.
Cotton RG; Human Variome Project Appelbe W Auerbach AD Becker K Bodmer W Boone DJ Boulyjenkov V Brahmachari S Brody L Brookes A Brown AF Byers P Cantu JM Cassiman JJ Claustres M Concannon P Cotton RG den Dunnen JT Flicek P Gibbs R Hall J Hasler J Katz M Kwok PY Laradi S Lindblom A Maglott D Marsh S Masimirembwa CM Minoshima S de Ramirez AM Pagon R Ramesar R Ravine D Richards S Rimoin D Ring HZ Scriver CR Sherry S Shimizu N Stein L Tadmouri GO Taylor G Watson M 《Nature genetics》2007,39(4):433-436
Lists of variations in genomic DNA and their effects have been kept for some time and have been used in diagnostics and research. Although these lists have been carefully gathered and curated, there has been little standardization and coordination, complicating their use. Given the myriad possible variations in the estimated 24,000 genes in the human genome, it would be useful to have standard criteria for databases of variation. Incomplete collection and ascertainment of variants demonstrates a need for a universally accessible system. These and other problems led to the World Heath Organization-cosponsored meeting on June 20-23, 2006 in Melbourne, Australia, which launched the Human Variome Project. This meeting addressed all areas of human genetics relevant to collection of information on variation and its effects. Members of each of eight sessions (the clinic and phenotype, the diagnostic laboratory, the research laboratory, curation and collection, informatics, relevance to the emerging world, integration and federation and funding and sustainability) developed a number of recommendations that were then organized into a total of 96 recommendations to act as a foundation for future work worldwide. Here we summarize the background of the project, the meeting and its recommendations. 相似文献
52.
Polar organisms have adapted their seasonal cycles to the dynamic interface between ice and water. This interface ranges from the micrometre-sized brine channels within sea ice to the planetary-scale advance and retreat of sea ice. Polar marine ecosystems are particularly sensitive to climate change because small temperature differences can have large effects on the extent and thickness of sea ice. Little is known about the interactions between large, long-lived organisms and their planktonic food supply. Disentangling the effects of human exploitation of upper trophic levels from basin-wide, decade-scale climate cycles to identify long-term, global trends is a daunting challenge facing polar bio-oceanography. 相似文献
53.
Jørgensen R Merrill AR Yates SP Marquez VE Schwan AL Boesen T Andersen GR 《Nature》2005,436(7053):979-984
The bacteria causing diphtheria, whooping cough, cholera and other diseases secrete mono-ADP-ribosylating toxins that modify intracellular proteins. Here, we describe four structures of a catalytically active complex between a fragment of Pseudomonas aeruginosa exotoxin A (ETA) and its protein substrate, translation elongation factor 2 (eEF2). The target residue in eEF2, diphthamide (a modified histidine), spans across a cleft and faces the two phosphates and a ribose of the non-hydrolysable NAD+ analogue, betaTAD. This suggests that the diphthamide is involved in triggering NAD+ cleavage and interacting with the proposed oxacarbenium intermediate during the nucleophilic substitution reaction, explaining the requirement of diphthamide for ADP ribosylation. Diphtheria toxin may recognize eEF2 in a manner similar to ETA. Notably, the toxin-bound betaTAD phosphates mimic the phosphate backbone of two nucleotides in a conformational switch of 18S rRNA, thereby achieving universal recognition of eEF2 by ETA. 相似文献
54.
Minocycline inhibits cytochrome c release and delays progression of amyotrophic lateral sclerosis in mice 总被引:56,自引:0,他引:56
Zhu S Stavrovskaya IG Drozda M Kim BY Ona V Li M Sarang S Liu AS Hartley DM Wu DC Gullans S Ferrante RJ Przedborski S Kristal BS Friedlander RM 《Nature》2002,417(6884):74-78
Minocycline mediates neuroprotection in experimental models of neurodegeneration. It inhibits the activity of caspase-1, caspase-3, inducible form of nitric oxide synthetase (iNOS) and p38 mitogen-activated protein kinase (MAPK). Although minocycline does not directly inhibit these enzymes, the effects may result from interference with upstream mechanisms resulting in their secondary activation. Because the above-mentioned factors are important in amyotrophic lateral sclerosis (ALS), we tested minocycline in mice with ALS. Here we report that minocycline delays disease onset and extends survival in ALS mice. Given the broad efficacy of minocycline, understanding its mechanisms of action is of great importance. We find that minocycline inhibits mitochondrial permeability-transition-mediated cytochrome c release. Minocycline-mediated inhibition of cytochrome c release is demonstrated in vivo, in cells, and in isolated mitochondria. Understanding the mechanism of action of minocycline will assist in the development and testing of more powerful and effective analogues. Because of the safety record of minocycline, and its ability to penetrate the blood-brain barrier, this drug may be a novel therapy for ALS. 相似文献
55.
56.
Caledophora gen. nov. is described based on two new species from New Caledonia, Caledophora irwini sp.nov. and Caledophora webbi sp.nov. This genus is similar to some genera from New Zealand, but can be differentiated from them by the combination of hypopygium not being expanded dorsoventrally, frons setation 4-4-4, light body colour and wing without vein R2+3. Its phylogenetic position is inferred to be within the Bothroprosopa-group of genera.
www.zoobank.org/urn:lsid:zoobank.org:pub:F6263E01-F2EF-4204-89D6-55BFD7A7AC00 相似文献
57.
Hatching chronology of Blue Grouse ( Dendragapus obscurus ) in northeastern Oregon was determined from 431 immatures examined from 1981 to 1985. Young hatched from 1 May through 8 July; median hatching dates for the five years ranged from 27 May to 5 June. Peak hatching in Oregon occurred from one to four weeks earlier than in most portions of the range of Blue Grouse but were similar to north central Washington and Idaho. Variations in hatching dates possibly were related to rainfall. 相似文献
58.
59.
Integrative genomics identifies MCU as an essential component of the mitochondrial calcium uniporter 总被引:2,自引:0,他引:2
Baughman JM Perocchi F Girgis HS Plovanich M Belcher-Timme CA Sancak Y Bao XR Strittmatter L Goldberger O Bogorad RL Koteliansky V Mootha VK 《Nature》2011,476(7360):341-345
Mitochondria from diverse organisms are capable of transporting large amounts of Ca(2+) via a ruthenium-red-sensitive, membrane-potential-dependent mechanism called the uniporter. Although the uniporter's biophysical properties have been studied extensively, its molecular composition remains elusive. We recently used comparative proteomics to identify MICU1 (also known as CBARA1), an EF-hand-containing protein that serves as a putative regulator of the uniporter. Here, we use whole-genome phylogenetic profiling, genome-wide RNA co-expression analysis and organelle-wide protein coexpression analysis to predict proteins functionally related to MICU1. All three methods converge on a novel predicted transmembrane protein, CCDC109A, that we now call 'mitochondrial calcium uniporter' (MCU). MCU forms oligomers in the mitochondrial inner membrane, physically interacts with MICU1, and resides within a large molecular weight complex. Silencing MCU in cultured cells or in vivo in mouse liver severely abrogates mitochondrial Ca(2+) uptake, whereas mitochondrial respiration and membrane potential remain fully intact. MCU has two predicted transmembrane helices, which are separated by a highly conserved linker facing the intermembrane space. Acidic residues in this linker are required for its full activity. However, an S259A point mutation retains function but confers resistance to Ru360, the most potent inhibitor of the uniporter. Our genomic, physiological, biochemical and pharmacological data firmly establish MCU as an essential component of the mitochondrial Ca(2+) uniporter. 相似文献
60.
Ressler KJ Mercer KB Bradley B Jovanovic T Mahan A Kerley K Norrholm SD Kilaru V Smith AK Myers AJ Ramirez M Engel A Hammack SE Toufexis D Braas KM Binder EB May V 《Nature》2011,470(7335):492-497
Pituitary adenylate cyclase-activating polypeptide (PACAP) is known to broadly regulate the cellular stress response. In contrast, it is unclear if the PACAP-PAC1 receptor pathway has a role in human psychological stress responses, such as post-traumatic stress disorder (PTSD). Here we find, in heavily traumatized subjects, a sex-specific association of PACAP blood levels with fear physiology, PTSD diagnosis and symptoms in females. We examined 44 single nucleotide polymorphisms (SNPs) spanning the PACAP (encoded by ADCYAP1) and PAC1 (encoded by ADCYAP1R1) genes, demonstrating a sex-specific association with PTSD. A single SNP in a putative oestrogen response element within ADCYAP1R1, rs2267735, predicts PTSD diagnosis and symptoms in females only. This SNP also associates with fear discrimination and with ADCYAP1R1 messenger RNA expression in human brain. Methylation of ADCYAP1R1 in peripheral blood is also associated with PTSD. Complementing these human data, ADCYAP1R1 mRNA is induced with fear conditioning or oestrogen replacement in rodent models. These data suggest that perturbations in the PACAP-PAC1 pathway are involved in abnormal stress responses underlying PTSD. These sex-specific effects may occur via oestrogen regulation of ADCYAP1R1. PACAP levels and ADCYAP1R1 SNPs may serve as useful biomarkers to further our mechanistic understanding of PTSD. 相似文献