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排序方式: 共有311条查询结果,搜索用时 15 毫秒
81.
Zanke BW Greenwood CM Rangrej J Kustra R Tenesa A Farrington SM Prendergast J Olschwang S Chiang T Crowdy E Ferretti V Laflamme P Sundararajan S Roumy S Olivier JF Robidoux F Sladek R Montpetit A Campbell P Bezieau S O'Shea AM Zogopoulos G Cotterchio M Newcomb P McLaughlin J Younghusband B Green R Green J Porteous ME Campbell H Blanche H Sahbatou M Tubacher E Bonaiti-Pellié C Buecher B Riboli E Kury S Chanock SJ Potter J Thomas G Gallinger S Hudson TJ Dunlop MG 《Nature genetics》2007,39(8):989-994
Using a multistage genetic association approach comprising 7,480 affected individuals and 7,779 controls, we identified markers in chromosomal region 8q24 associated with colorectal cancer. In stage 1, we genotyped 99,632 SNPs in 1,257 affected individuals and 1,336 controls from Ontario. In stages 2-4, we performed serial replication studies using 4,024 affected individuals and 4,042 controls from Seattle, Newfoundland and Scotland. We identified one locus on chromosome 8q24 and another on 9p24 having combined odds ratios (OR) for stages 1-4 of 1.18 (trend; P = 1.41 x 10(-8)) and 1.14 (trend; P = 1.32 x 10(-5)), respectively. Additional analyses in 2,199 affected individuals and 2,401 controls from France and Europe supported the association at the 8q24 locus (OR = 1.16, trend; 95% confidence interval (c.i.): 1.07-1.26; P = 5.05 x 10(-4)). A summary across all seven studies at the 8q24 locus was highly significant (OR = 1.17, c.i.: 1.12-1.23; P = 3.16 x 10(-11)). This locus has also been implicated in prostate cancer. 相似文献
82.
Abecasis G Tam PK Bustamante CD Ostrander EA Scherer SW Chanock SJ Kwok PY Brookes AJ 《Nature genetics》2007,39(2):153-155
The eighth annual Human Genome Variation Meeting was held in September 2006 in the Hong Kong Special Administrative Region, China. The meeting highlighted recent advances in characterization of genetic variation, including genome-wide association studies and structural variation. 相似文献
83.
Sun L Rommens JM Corvol H Li W Li X Chiang TA Lin F Dorfman R Busson PF Parekh RV Zelenika D Blackman SM Corey M Doshi VK Henderson L Naughton KM O'Neal WK Pace RG Stonebraker JR Wood SD Wright FA Zielenski J Clement A Drumm ML Boëlle PY Cutting GR Knowles MR Durie PR Strug LJ 《Nature genetics》2012,44(5):562-569
Variants associated with meconium ileus in cystic fibrosis were identified in 3,763 affected individuals by genome-wide association study (GWAS). Five SNPs at two loci near SLC6A14 at Xq23-24 (minimum P = 1.28 × 10(-12) at rs3788766) and SLC26A9 at 1q32.1 (minimum P = 9.88 × 10(-9) at rs4077468) accounted for ~5% of phenotypic variability and were replicated in an independent sample of affected individuals (n = 2,372; P = 0.001 and 0.0001, respectively). By incorporating the knowledge that disease-causing mutations in CFTR alter electrolyte and fluid flux across surface epithelium into a hypothesis-driven GWAS (GWAS-HD), we identified associations with the same SNPs in SLC6A14 and SLC26A9 and established evidence for the involvement of SNPs in a third solute carrier gene, SLC9A3. In addition, GWAS-HD provided evidence of association between meconium ileus and multiple genes encoding constituents of the apical plasma membrane where CFTR resides (P = 0.0002; testing of 155 apical membrane genes jointly and in replication, P = 0.022). These findings suggest that modulating activities of apical membrane constituents could complement current therapeutic paradigms for cystic fibrosis. 相似文献
84.
Le Chalony C Hoffschir F Gauthier LR Gross J Biard DS Boussin FD Pennaneach V 《Cellular and molecular life sciences : CMLS》2012,69(17):2933-2949
DNA ligase I (LigI) plays a central role in the joining of strand interruptions during replication and repair. In our current study, we provide evidence that DNA ligase III (LigIII) and XRCC1, which form a complex that functions in single-strand break repair, are required for the proliferation of mammalian LigI-depleted cells. We show from our data that in cells with either dysfunctional LigI activity or depleted of this enzyme, both LigIII and XRCC1 are retained on the chromatin and accumulate at replication foci. We also demonstrate that the LigI and LigIII proteins cooperate to inhibit sister chromatid exchanges but that only LigI prevents telomere sister fusions. Taken together, these results suggest that in cells with dysfunctional LigI, LigIII contributes to the ligation of replication intermediates but not to the prevention of telomeric instability. 相似文献
85.
Reynaud CA Descatoire M Dogan I Huetz F Weller S Weill JC 《Cellular and molecular life sciences : CMLS》2012,69(10):1625-1634
Humoral memory is maintained by two types of persistent cells, memory B cells and plasma cells, which have different phenotypes
and functions. Long-lived plasma cells can survive for a lifespan within a complex niche in the bone marrow and provide continuous
protective serum antibody levels. Memory B cells reside in secondary lymphoid organs, where they can be rapidly mobilized
upon a new antigenic encounter. Surface IgG has long been taken as a surrogate marker for memory in the mouse. Recently, however,
we have brought evidence for a long-lived IgM memory B cell population in the mouse, while we have also argued that, in humans,
these same cells are not classical memory B cells but marginal zone (MZ) B cells which, as opposed to their mouse MZ counterpart,
recirculate and carry a mutated B cell receptor. In this review, we will discuss these apparently paradoxical results. 相似文献
86.
Identification of ten loci associated with height highlights new biological pathways in human growth 总被引:1,自引:0,他引:1
Lettre G Jackson AU Gieger C Schumacher FR Berndt SI Sanna S Eyheramendy S Voight BF Butler JL Guiducci C Illig T Hackett R Heid IM Jacobs KB Lyssenko V Uda M;Diabetes Genetics Initiative;FUSION;KORA;Prostate Lung Colorectal Ovarian Cancer Screening Trial;Nurses' Health Study;SardiNIA Boehnke M Chanock SJ Groop LC Hu FB Isomaa B Kraft P Peltonen L Salomaa V Schlessinger D Hunter DJ Hayes RB Abecasis GR Wichmann HE Mohlke KL Hirschhorn JN 《Nature genetics》2008,40(5):584-591
Height is a classic polygenic trait, reflecting the combined influence of multiple as-yet-undiscovered genetic factors. We carried out a meta-analysis of genome-wide association study data of height from 15,821 individuals at 2.2 million SNPs, and followed up the strongest findings in >10,000 subjects. Ten newly identified and two previously reported loci were strongly associated with variation in height (P values from 4 x 10(-7) to 8 x 10(-22)). Together, these 12 loci account for approximately 2% of the population variation in height. Individuals with < or =8 height-increasing alleles and > or =16 height-increasing alleles differ in height by approximately 3.5 cm. The newly identified loci, along with several additional loci with strongly suggestive associations, encompass both strong biological candidates and unexpected genes, and highlight several pathways (let-7 targets, chromatin remodeling proteins and Hedgehog signaling) as important regulators of human stature. These results expand the picture of the biological regulation of human height and of the genetic architecture of this classical complex trait. 相似文献
87.
Meriem El Ghachi Nicole Howe Rodolphe Auger Alexandre Lambion Annick Guiseppi François Delbrassine Guillaume Manat Sophie Roure Sabine Peslier Eric Sauvage Lutz Vogeley Juan-Carlos Rengifo-Gonzalez Paulette Charlier Dominique Mengin-Lecreulx Maryline Foglino Thierry Touzé Martin Caffrey Frédéric Kerff 《Cellular and molecular life sciences : CMLS》2017,74(12):2319-2332
Type 2 phosphatidic acid phosphatases (PAP2s) can be either soluble or integral membrane enzymes. In bacteria, integral membrane PAP2s play major roles in the metabolisms of glycerophospholipids, undecaprenyl-phosphate (C55-P) lipid carrier and lipopolysaccharides. By in vivo functional experiments and biochemical characterization we show that the membrane PAP2 coded by the Bacillus subtilis yodM gene is the principal phosphatidylglycerol phosphate (PGP) phosphatase of B. subtilis. We also confirm that this enzyme, renamed bsPgpB, has a weaker activity on C55-PP. Moreover, we solved the crystal structure of bsPgpB at 2.25 Å resolution, with tungstate (a phosphate analog) in the active site. The structure reveals two lipid chains in the active site vicinity, allowing for PGP substrate modeling and molecular dynamic simulation. Site-directed mutagenesis confirmed the residues important for substrate specificity, providing a basis for predicting the lipids preferentially dephosphorylated by membrane PAP2s. 相似文献
88.
89.
Sieburth D Ch'ng Q Dybbs M Tavazoie M Kennedy S Wang D Dupuy D Rual JF Hill DE Vidal M Ruvkun G Kaplan JM 《Nature》2005,436(7050):510-517
Chemical synapses are complex structures that mediate rapid intercellular signalling in the nervous system. Proteomic studies suggest that several hundred proteins will be found at synaptic specializations. Here we describe a systematic screen to identify genes required for the function or development of Caenorhabditis elegans neuromuscular junctions. A total of 185 genes were identified in an RNA interference screen for decreased acetylcholine secretion; 132 of these genes had not previously been implicated in synaptic transmission. Functional profiles for these genes were determined by comparing secretion defects observed after RNA interference under a variety of conditions. Hierarchical clustering identified groups of functionally related genes, including those involved in the synaptic vesicle cycle, neuropeptide signalling and responsiveness to phorbol esters. Twenty-four genes encoded proteins that were localized to presynaptic specializations. Loss-of-function mutations in 12 genes caused defects in presynaptic structure. 相似文献
90.
Toppani A Robert F Libourel G de Donato P Barres O d'Hendecourt L Ghanbaja J 《Nature》2005,437(7062):1121-1124
The signature of carbonate minerals has long been suspected in the mid-infrared spectra of various astrophysical environments such as protostars. Abiogenic carbonates are considered as indicators of aqueous mineral alteration in the presence of CO2-rich liquid water. The recent claimed detection of calcite associated with amorphous silicates in two planetary nebulae and protostars devoid of planetary bodies questions the relevance of this indicator; but in the absence of an alternative mode of formation under circumstellar conditions, this detection remains controversial. The main dust component observed in circumstellar envelopes is amorphous silicates, which are thought to have formed by non-equilibrium condensation. Here we report experiments demonstrating that carbonates can be formed with amorphous silicates during the non-equilibrium condensation of a silicate gas in a H2O-CO2-rich vapour. We propose that the observed astrophysical carbonates have condensed in H2O(g)-CO2(g)-rich, high-temperature and high-density regions such as evolved stellar winds, or those induced by grain sputtering upon shocks in protostellar outflows. 相似文献