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排序方式: 共有230条查询结果,搜索用时 343 毫秒
211.
Parvari R Hershkovitz E Grossman N Gorodischer R Loeys B Zecic A Mortier G Gregory S Sharony R Kambouris M Sakati N Meyer BF Al Aqeel AI Al Humaidan AK Al Zanhrani F Al Swaid A Al Othman J Diaz GA Weiner R Khan KT Gordon R Gelb BD;HRD/Autosomal Recessive Kenny-Caffey Syndrome Consortium 《Nature genetics》2002,32(3):448-452
The syndrome of congenital hypoparathyroidism, mental retardation, facial dysmorphism and extreme growth failure (HRD or Sanjad-Sakati syndrome; OMIM 241410) is an autosomal recessive disorder reported almost exclusively in Middle Eastern populations. A similar syndrome with the additional features of osteosclerosis and recurrent bacterial infections has been classified as autosomal recessive Kenny-Caffey syndrome (AR-KCS; OMIM 244460). Both traits have previously been mapped to chromosome 1q43-44 (refs 5,6) and, despite the observed clinical variability, share an ancestral haplotype, suggesting a common founder mutation. We describe refinement of the critical region to an interval of roughly 230 kb and identification of deletion and truncation mutations of TBCE in affected individuals. The gene TBCE encodes one of several chaperone proteins required for the proper folding of alpha-tubulin subunits and the formation of alpha-beta-tubulin heterodimers. Analysis of diseased fibroblasts and lymphoblastoid cells showed lower microtubule density at the microtubule-organizing center (MTOC) and perturbed microtubule polarity in diseased cells. Immunofluorescence and ultrastructural studies showed disturbances in subcellular organelles that require microtubules for membrane trafficking, such as the Golgi and late endosomal compartments. These findings demonstrate that HRD and AR-KCS are chaperone diseases caused by a genetic defect in the tubulin assembly pathway, and establish a potential connection between tubulin physiology and the development of the parathyroid. 相似文献
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216.
Transcriptional regulatory code of a eukaryotic genome 总被引:2,自引:0,他引:2
217.
Martin J Han C Gordon LA Terry A Prabhakar S She X Xie G Hellsten U Chan YM Altherr M Couronne O Aerts A Bajorek E Black S Blumer H Branscomb E Brown NC Bruno WJ Buckingham JM Callen DF Campbell CS Campbell ML Campbell EW Caoile C Challacombe JF Chasteen LA Chertkov O Chi HC Christensen M Clark LM Cohn JD Denys M Detter JC Dickson M Dimitrijevic-Bussod M Escobar J Fawcett JJ Flowers D Fotopulos D Glavina T Gomez M Gonzales E Goodstein D Goodwin LA Grady DL Grigoriev I Groza M Hammon N Hawkins T 《Nature》2004,432(7020):988-994
218.
Grimwood J Gordon LA Olsen A Terry A Schmutz J Lamerdin J Hellsten U Goodstein D Couronne O Tran-Gyamfi M Aerts A Altherr M Ashworth L Bajorek E Black S Branscomb E Caenepeel S Carrano A Caoile C Chan YM Christensen M Cleland CA Copeland A Dalin E Dehal P Denys M Detter JC Escobar J Flowers D Fotopulos D Garcia C Georgescu AM Glavina T Gomez M Gonzales E Groza M Hammon N Hawkins T Haydu L Ho I Huang W Israni S Jett J Kadner K Kimball H Kobayashi A Larionov V Leem SH Lopez F Lou Y Lowry S 《Nature》2004,428(6982):529-535
Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G + C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu. 相似文献
219.
A large amount (about three solar masses) of cold (18 K) dust in the prototypical type II supernova remnant Cassiopeia A was recently reported. It was concluded that dust production in type II supernovae can explain how the large quantities (approximately 10(8) solar masses) of dust observed in the most distant quasars could have been produced within only 700 million years after the Big Bang. Foreground clouds of interstellar material, however, complicate the interpretation of the earlier submillimetre observations of Cas A. Here we report far-infrared and molecular line observations that demonstrate that most of the detected submillimetre emission originates from interstellar dust in a molecular cloud complex located in the line of sight between the Earth and Cas A, and is therefore not associated with the remnant. The argument that type II supernovae produce copious amounts of dust is not supported by the case of Cas A, which previously appeared to provide the best evidence for this possibility. 相似文献
220.
Beja-Pereira A Luikart G England PR Bradley DG Jann OC Bertorelle G Chamberlain AT Nunes TP Metodiev S Ferrand N Erhardt G 《Nature genetics》2003,35(4):311-313
Milk from domestic cows has been a valuable food source for over 8,000 years, especially in lactose-tolerant human societies that exploit dairy breeds. We studied geographic patterns of variation in genes encoding the six most important milk proteins in 70 native European cattle breeds. We found substantial geographic coincidence between high diversity in cattle milk genes, locations of the European Neolithic cattle farming sites (>5,000 years ago) and present-day lactose tolerance in Europeans. This suggests a gene-culture coevolution between cattle and humans. 相似文献