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排序方式: 共有400条查询结果,搜索用时 234 毫秒
21.
Elia J Glessner JT Wang K Takahashi N Shtir CJ Hadley D Sleiman PM Zhang H Kim CE Robison R Lyon GJ Flory JH Bradfield JP Imielinski M Hou C Frackelton EC Chiavacci RM Sakurai T Rabin C Middleton FA Thomas KA Garris M Mentch F Freitag CM Steinhausen HC Todorov AA Reif A Rothenberger A Franke B Mick EO Roeyers H Buitelaar J Lesch KP Banaschewski T Ebstein RP Mulas F Oades RD Sergeant J Sonuga-Barke E Renner TJ Romanos M Romanos J Warnke A Walitza S Meyer J Pálmason H Seitz C Loo SK Smalley SL 《Nature genetics》2012,44(1):78-84
Attention deficit hyperactivity disorder (ADHD) is a common, heritable neuropsychiatric disorder of unknown etiology. We performed a whole-genome copy number variation (CNV) study on 1,013 cases with ADHD and 4,105 healthy children of European ancestry using 550,000 SNPs. We evaluated statistically significant findings in multiple independent cohorts, with a total of 2,493 cases with ADHD and 9,222 controls of European ancestry, using matched platforms. CNVs affecting metabotropic glutamate receptor genes were enriched across all cohorts (P = 2.1 × 10(-9)). We saw GRM5 (encoding glutamate receptor, metabotropic 5) deletions in ten cases and one control (P = 1.36 × 10(-6)). We saw GRM7 deletions in six cases, and we saw GRM8 deletions in eight cases and no controls. GRM1 was duplicated in eight cases. We experimentally validated the observed variants using quantitative RT-PCR. A gene network analysis showed that genes interacting with the genes in the GRM family are enriched for CNVs in ~10% of the cases (P = 4.38 × 10(-10)) after correction for occurrence in the controls. We identified rare recurrent CNVs affecting glutamatergic neurotransmission genes that were overrepresented in multiple ADHD cohorts. 相似文献
22.
Estimating the proportion of variation in susceptibility to schizophrenia captured by common SNPs 总被引:1,自引:0,他引:1
Lee SH DeCandia TR Ripke S Yang J;Schizophrenia Psychiatric Genome-Wide Association Study Consortium 《Nature genetics》2012,44(3):247-250
Schizophrenia is a complex disorder caused by both genetic and environmental factors. Using 9,087 affected individuals, 12,171 controls and 915,354 imputed SNPs from the Schizophrenia Psychiatric Genome-Wide Association Study (GWAS) Consortium (PGC-SCZ), we estimate that 23% (s.e. = 1%) of variation in liability to schizophrenia is captured by SNPs. We show that a substantial proportion of this variation must be the result of common causal variants, that the variance explained by each chromosome is linearly related to its length (r = 0.89, P = 2.6 × 10(-8)), that the genetic basis of schizophrenia is the same in males and females, and that a disproportionate proportion of variation is attributable to a set of 2,725 genes expressed in the central nervous system (CNS; P = 7.6 × 10(-8)). These results are consistent with a polygenic genetic architecture and imply more individual SNP associations will be detected for this disease as sample size increases. 相似文献
23.
Microtubules are cytoskeletal polymers of tubulin involved in many cellular functions. Their dynamic instability is controlled by numerous compounds and proteins, including colchicine and stathmin family proteins. The way in which microtubule instability is regulated at the molecular level has remained elusive, mainly because of the lack of appropriate structural data. Here, we present the structure, at 3.5 A resolution, of tubulin in complex with colchicine and with the stathmin-like domain (SLD) of RB3. It shows the interaction of RB3-SLD with two tubulin heterodimers in a curved complex capped by the SLD amino-terminal domain, which prevents the incorporation of the complexed tubulin into microtubules. A comparison with the structure of tubulin in protofilaments shows changes in the subunits of tubulin as it switches from its straight conformation to a curved one. These changes correlate with the loss of lateral contacts and provide a rationale for the rapid microtubule depolymerization characteristic of dynamic instability. Moreover, the tubulin-colchicine complex sheds light on the mechanism of colchicine's activity: we show that colchicine binds at a location where it prevents curved tubulin from adopting a straight structure, which inhibits assembly. 相似文献
24.
The construction of stable blood vessels is a fundamental challenge for tissue engineering in regenerative medicine. Although certain genes can be introduced into vascular cells to enhance their survival and proliferation, these manipulations may be oncogenic. We show here that a network of long-lasting blood vessels can be formed in mice by co-implantation of vascular endothelial cells and mesenchymal precursor cells, by-passing the need for risky genetic manipulations. These networks are stable and functional for one year in vivo. 相似文献
25.
Ding H Wu X Boström H Kim I Wong N Tsoi B O'Rourke M Koh GY Soriano P Betsholtz C Hart TC Marazita ML Field LL Tam PP Nagy A 《Nature genetics》2004,36(10):1111-1116
PDGF-C is a member of the platelet-derived growth factor (PDGF) family, which signals through PDGF receptor (PDGFR) alphaalpha and alphabeta dimers. Here we show that Pdgfc(-/-) mice die in the perinatal period owing to feeding and respiratory difficulties associated with a complete cleft of the secondary palate. This phenotype was less severe than that of Pdgfra(-/-) embryos. Pdgfc(-/-) Pdgfa(-/-) embryos developed a cleft face, subepidermal blistering, deficiency of renal cortex mesenchyme, spina bifida and skeletal and vascular defects. Complete loss of function of both ligands, therefore, phenocopied the loss of PDGFR-alpha function, suggesting that both PDGF-A and PDGF-C signal through PDGFR-alpha to regulate the development of craniofacial structures, the neural tube and mesodermal organs. Our results also show that PDGF-C signaling is a new pathway in palatogenesis, different from, and independent of, those previously implicated. 相似文献
26.
Davila S Furu L Gharavi AG Tian X Onoe T Qian Q Li A Cai Y Kamath PS King BF Azurmendi PJ Tahvanainen P Kääriäinen H Höckerstedt K Devuyst O Pirson Y Martin RS Lifton RP Tahvanainen E Torres VE Somlo S 《Nature genetics》2004,36(6):575-577
Mutations in PRKCSH, encoding the beta-subunit of glucosidase II, an N-linked glycan-processing enzyme in the endoplasmic reticulum (ER), cause autosomal dominant polycystic liver disease. We found that mutations in SEC63, encoding a component of the protein translocation machinery in the ER, also cause this disease. These findings are suggestive of a role for cotranslational protein-processing pathways in maintaining epithelial luminal structure and implicate noncilial ER proteins in human polycystic disease. 相似文献
27.
28.
Bird AW Yu DY Pray-Grant MG Qiu Q Harmon KE Megee PC Grant PA Smith MM Christman MF 《Nature》2002,419(6905):411-415
29.
Hon WC Wilson MI Harlos K Claridge TD Schofield CJ Pugh CW Maxwell PH Ratcliffe PJ Stuart DI Jones EY 《Nature》2002,417(6892):975-978
30.
Kapfhamer D Valladares O Sun Y Nolan PM Rux JJ Arnold SE Veasey SC Bućan M 《Nature genetics》2002,32(2):290-295
Rab3a is the most abundant Rab (ras-associated binding) protein in the brain and has a regulatory role in synaptic vesicle trafficking. Mice with a targeted loss-of-function mutation in Rab3a have defects in Ca(2+)-dependent synaptic transmission: the number of vesicles released in response to an action potential is greater than in wildtype mice, resulting in greater synaptic depression and the abolishment of CA3 mossy-fiber long term potentiation. The effect of these changes on behavior is unknown. In a screen for mouse mutants with abnormal rest-activity and sleep patterns, we identified a semidominant mutation, called earlybird, that shortens the circadian period of locomotor activity. Sequence analysis of Rab3a identified a point mutation in the conserved amino acid (Asp77Gly) within the GTP-binding domain of this protein in earlybird mutants, resulting in significantly reduced levels of Rab3a protein. Phenotypic assessment of earlybird mice and a null allele of Rab3a revealed anomalies in circadian period and sleep homeostasis, providing evidence that Rab3a-mediated synaptic transmission is involved in these behaviors. 相似文献