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排序方式: 共有399条查询结果,搜索用时 15 毫秒
101.
Rohmann E Brunner HG Kayserili H Uyguner O Nürnberg G Lew ED Dobbie A Eswarakumar VP Uzumcu A Ulubil-Emeroglu M Leroy JG Li Y Becker C Lehnerdt K Cremers CW Yüksel-Apak M Nürnberg P Kubisch C Kubisch C Schlessinger J van Bokhoven H Wollnik B 《Nature genetics》2006,38(4):414-417
Lacrimo-auriculo-dento-digital (LADD) syndrome is characterized by lacrimal duct aplasia, malformed ears and deafness, small teeth and digital anomalies. We identified heterozygous mutations in the tyrosine kinase domains of the genes encoding fibroblast growth factor receptors 2 and 3 (FGFR2, FGFR3) in LADD families, and in one further LADD family, we detected a mutation in the gene encoding fibroblast growth factor 10 (FGF10), a known FGFR ligand. These findings increase the spectrum of anomalies associated with abnormal FGF signaling. 相似文献
102.
Germline KRAS mutations cause Noonan syndrome 总被引:22,自引:0,他引:22
Schubbert S Zenker M Rowe SL Böll S Klein C Bollag G van der Burgt I Musante L Kalscheuer V Wehner LE Nguyen H West B Zhang KY Sistermans E Rauch A Niemeyer CM Shannon K Kratz CP 《Nature genetics》2006,38(3):331-336
Noonan syndrome (MIM 163950) is characterized by short stature, facial dysmorphism and cardiac defects. Heterozygous mutations in PTPN11, which encodes SHP-2, cause approximately 50% of cases of Noonan syndrome. The SHP-2 phosphatase relays signals from activated receptor complexes to downstream effectors, including Ras. We discovered de novo germline KRAS mutations that introduce V14I, T58I or D153V amino acid substitutions in five individuals with Noonan syndrome and a P34R alteration in a individual with cardio-facio-cutaneous syndrome (MIM 115150), which has overlapping features with Noonan syndrome. Recombinant V14I and T58I K-Ras proteins show defective intrinsic GTP hydrolysis and impaired responsiveness to GTPase activating proteins, render primary hematopoietic progenitors hypersensitive to growth factors and deregulate signal transduction in a cell lineage-specific manner. These studies establish germline KRAS mutations as a cause of human disease and infer that the constellation of developmental abnormalities seen in Noonan syndrome spectrum is, in large part, due to hyperactive Ras. 相似文献
103.
Gain-of-function RAF1 mutations cause Noonan and LEOPARD syndromes with hypertrophic cardiomyopathy 总被引:14,自引:0,他引:14
Pandit B Sarkozy A Pennacchio LA Carta C Oishi K Martinelli S Pogna EA Schackwitz W Ustaszewska A Landstrom A Bos JM Ommen SR Esposito G Lepri F Faul C Mundel P López Siguero JP Tenconi R Selicorni A Rossi C Mazzanti L Torrente I Marino B Digilio MC Zampino G Ackerman MJ Dallapiccola B Tartaglia M Gelb BD 《Nature genetics》2007,39(8):1007-1012
Noonan and LEOPARD syndromes are developmental disorders with overlapping features, including cardiac abnormalities, short stature and facial dysmorphia. Increased RAS signaling owing to PTPN11, SOS1 and KRAS mutations causes approximately 60% of Noonan syndrome cases, and PTPN11 mutations cause 90% of LEOPARD syndrome cases. Here, we report that 18 of 231 individuals with Noonan syndrome without known mutations (corresponding to 3% of all affected individuals) and two of six individuals with LEOPARD syndrome without PTPN11 mutations have missense mutations in RAF1, which encodes a serine-threonine kinase that activates MEK1 and MEK2. Most mutations altered a motif flanking Ser259, a residue critical for autoinhibition of RAF1 through 14-3-3 binding. Of 19 subjects with a RAF1 mutation in two hotspots, 18 (or 95%) showed hypertrophic cardiomyopathy (HCM), compared with the 18% prevalence of HCM among individuals with Noonan syndrome in general. Ectopically expressed RAF1 mutants from the two HCM hotspots had increased kinase activity and enhanced ERK activation, whereas non-HCM-associated mutants were kinase impaired. Our findings further implicate increased RAS signaling in pathological cardiomyocyte hypertrophy. 相似文献
104.
Christian Marx 《Archive for History of Exact Sciences》2012,66(5):531-555
In Book 8 of his Geographike Hyphegesis Ptolemy gives coordinates for ca. 360 so-called noteworthy cities. These coordinates are the time difference to Alexandria, the length of the longest day, and partly the ecliptic distance from the summer solstice. The supposable original conversions between the coordinates in Book 8 and the geographical coordinates in the location catalogue of Books 2–7 including the underlying parameters and tabulations are here reconstructed. The results document the differences between the ${\Omega}$ - and ${\Xi}$ -recension. The known difference in the longitude of Alexandria underlying the conversion of the longitudes is examined more closely. For the ecliptic distances from the summer solstice of the ${\Omega}$ -recension, it is revealed that they were originally computed by means of a so far undiscovered approximate, linear conversion. Further it is shown that the lengths of the longest day could be based on a linear interpolation of the data in the Mathematike Syntaxis 2.6. 相似文献
105.
Floriano?Rodrigues Imke?Schmidt Christian?Kl?mbtEmail author 《Cellular and molecular life sciences : CMLS》2011,68(1):55-69
In all complex organisms, the peripheral nerves ensure the portage of information from the periphery to central computing
and back again. Axons are in part amazingly long and are accompanied by several different glial cell types. These peripheral
glial cells ensure electrical conductance, most likely nuture the long axon, and establish and maintain a barrier towards
extracellular body fluids. Recent work has revealed a surprisingly similar organization of peripheral nerves of vertebrates
and Drosophila. Thus, the genetic dissection of glial differentiation in Drosophila may also advance our understanding of basic principles underlying the development of peripheral nerves in vertebrates. 相似文献
106.
Hoischen A van Bon BW Rodríguez-Santiago B Gilissen C Vissers LE de Vries P Janssen I van Lier B Hastings R Smithson SF Newbury-Ecob R Kjaergaard S Goodship J McGowan R Bartholdi D Rauch A Peippo M Cobben JM Wieczorek D Gillessen-Kaesbach G Veltman JA Brunner HG de Vries BB 《Nature genetics》2011,43(8):729-731
Bohring-Opitz syndrome is characterized by severe intellectual disability, distinctive facial features and multiple congenital malformations. We sequenced the exomes of three individuals with Bohring-Opitz syndrome and in each identified heterozygous de novo nonsense mutations in ASXL1, which is required for maintenance of both activation and silencing of Hox genes. In total, 7 out of 13 subjects with a Bohring-Opitz phenotype had de novo ASXL1 mutations, suggesting that the syndrome is genetically heterogeneous. 相似文献
107.
Lausch E Janecke A Bros M Trojandt S Alanay Y De Laet C Hübner CA Meinecke P Nishimura G Matsuo M Hirano Y Tenoutasse S Kiss A Rosa RF Unger SL Renella R Bonafé L Spranger J Unger S Zabel B Superti-Furga A 《Nature genetics》2011,43(2):132-137
Vertebral and metaphyseal dysplasia, spasticity with cerebral calcifications, and strong predisposition to autoimmune diseases are the hallmarks of the genetic disorder spondyloenchondrodysplasia. We mapped a locus in five consanguineous families to chromosome 19p13 and identified mutations in ACP5, which encodes tartrate-resistant phosphatase (TRAP), in 14 affected individuals and showed that these mutations abolish enzyme function in the serum and cells of affected individuals. Phosphorylated osteopontin, a protein involved in bone reabsorption and in immune regulation, accumulates in serum, urine and cells cultured from TRAP-deficient individuals. Case-derived dendritic cells exhibit an altered cytokine profile and are more potent than matched control cells in stimulating allogeneic T cell proliferation in mixed lymphocyte reactions. These findings shed new light on the role of osteopontin and its regulation by TRAP in the pathogenesis of common autoimmune disorders. 相似文献
108.
Locasale JW Grassian AR Melman T Lyssiotis CA Mattaini KR Bass AJ Heffron G Metallo CM Muranen T Sharfi H Sasaki AT Anastasiou D Mullarky E Vokes NI Sasaki M Beroukhim R Stephanopoulos G Ligon AH Meyerson M Richardson AL Chin L Wagner G Asara JM Brugge JS Cantley LC Vander Heiden MG 《Nature genetics》2011,43(9):869-874
Most tumors exhibit increased glucose metabolism to lactate, however, the extent to which glucose-derived metabolic fluxes are used for alternative processes is poorly understood. Using a metabolomics approach with isotope labeling, we found that in some cancer cells a relatively large amount of glycolytic carbon is diverted into serine and glycine metabolism through phosphoglycerate dehydrogenase (PHGDH). An analysis of human cancers showed that PHGDH is recurrently amplified in a genomic region of focal copy number gain most commonly found in melanoma. Decreasing PHGDH expression impaired proliferation in amplified cell lines. Increased expression was also associated with breast cancer subtypes, and ectopic expression of PHGDH in mammary epithelial cells disrupted acinar morphogenesis and induced other phenotypic alterations that may predispose cells to transformation. Our findings show that the diversion of glycolytic flux into a specific alternate pathway can be selected during tumor development and may contribute to the pathogenesis of human cancer. 相似文献
109.
Sequence variants in IL10, ARPC2 and multiple other loci contribute to ulcerative colitis susceptibility 总被引:1,自引:0,他引:1
Franke A Balschun T Karlsen TH Sventoraityte J Nikolaus S Mayr G Domingues FS Albrecht M Nothnagel M Ellinghaus D Sina C Onnie CM Weersma RK Stokkers PC Wijmenga C Gazouli M Strachan D McArdle WL Vermeire S Rutgeerts P Rosenstiel P Krawczak M Vatn MH;IBSEN study group Mathew CG Schreiber S 《Nature genetics》2008,40(11):1319-1323
Inflammatory bowel disease (IBD) typically manifests as either ulcerative colitis (UC) or Crohn's disease (CD). Systematic identification of susceptibility genes for IBD has thus far focused mainly on CD, and little is known about the genetic architecture of UC. Here we report a genome-wide association study with 440,794 SNPs genotyped in 1,167 individuals with UC and 777 healthy controls. Twenty of the most significantly associated SNPs were tested for replication in three independent European case-control panels comprising a total of 1,855 individuals with UC and 3,091 controls. Among the four consistently replicated markers, SNP rs3024505 immediately flanking the IL10 (interleukin 10) gene on chromosome 1q32.1 showed the most significant association in the combined verification samples (P = 1.35 x 10(-12); OR = 1.46 (1.31-1.62)). The other markers were located in ARPC2 and in the HLA-BTNL2 region. Association between rs3024505 and CD (1,848 cases, 1,804 controls) was weak (P = 0.013; OR = 1.17 (1.01-1.34)). IL10 is an immunosuppressive cytokine that has long been proposed to influence IBD pathophysiology. Our findings strongly suggest that defective IL10 function is central to the pathogenesis of the UC subtype of IBD. 相似文献
110.
Frøkjaer-Jensen C Davis MW Hopkins CE Newman BJ Thummel JM Olesen SP Grunnet M Jorgensen EM 《Nature genetics》2008,40(11):1375-1383
At present, transgenes in Caenorhabditis elegans are generated by injecting DNA into the germline. The DNA assembles into a semistable extrachromosomal array composed of many copies of injected DNA. These transgenes are typically overexpressed in somatic cells and silenced in the germline. We have developed a method that inserts a single copy of a transgene into a defined site. Mobilization of a Mos1 transposon generates a double-strand break in noncoding DNA. The break is repaired by copying DNA from an extrachromosomal template into the chromosomal site. Homozygous single-copy insertions can be obtained in less than 2 weeks by injecting approximately 20 worms. We have successfully inserted transgenes as long as 9 kb and verified that single copies are inserted at the targeted site. Single-copy transgenes are expressed at endogenous levels and can be expressed in the female and male germlines. 相似文献