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271.
Mutations in the gene encoding the basal body protein RPGRIP1L, a nephrocystin-4 interactor, cause Joubert syndrome 总被引:7,自引:0,他引:7
Arts HH Doherty D van Beersum SE Parisi MA Letteboer SJ Gorden NT Peters TA Märker T Voesenek K Kartono A Ozyurek H Farin FM Kroes HY Wolfrum U Brunner HG Cremers FP Glass IA Knoers NV Roepman R 《Nature genetics》2007,39(7):882-888
Protein-protein interaction analyses have uncovered a ciliary and basal body protein network that, when disrupted, can result in nephronophthisis (NPHP), Leber congenital amaurosis, Senior-L?ken syndrome (SLSN) or Joubert syndrome (JBTS). However, details of the molecular mechanisms underlying these disorders remain poorly understood. RPGRIP1-like protein (RPGRIP1L) is a homolog of RPGRIP1 (RPGR-interacting protein 1), a ciliary protein defective in Leber congenital amaurosis. We show that RPGRIP1L interacts with nephrocystin-4 and that mutations in the gene encoding nephrocystin-4 (NPHP4) that are known to cause SLSN disrupt this interaction. RPGRIP1L is ubiquitously expressed, and its protein product localizes to basal bodies. Therefore, we analyzed RPGRIP1L as a candidate gene for JBTS and identified loss-of-function mutations in three families with typical JBTS, including the characteristic mid-hindbrain malformation. This work identifies RPGRIP1L as a gene responsible for JBTS and establishes a central role for cilia and basal bodies in the pathophysiology of this disorder. 相似文献
272.
A genome-wide association study for celiac disease identifies risk variants in the region harboring IL2 and IL21 总被引:14,自引:0,他引:14
van Heel DA Franke L Hunt KA Gwilliam R Zhernakova A Inouye M Wapenaar MC Barnardo MC Bethel G Holmes GK Feighery C Jewell D Kelleher D Kumar P Travis S Walters JR Sanders DS Howdle P Swift J Playford RJ McLaren WM Mearin ML Mulder CJ McManus R McGinnis R Cardon LR Deloukas P Wijmenga C 《Nature genetics》2007,39(7):827-829
We tested 310,605 SNPs for association in 778 individuals with celiac disease and 1,422 controls. Outside the HLA region, the most significant finding (rs13119723; P = 2.0 x 10(-7)) was in the KIAA1109-TENR-IL2-IL21 linkage disequilibrium block. We independently confirmed association in two further collections (strongest association at rs6822844, 24 kb 5' of IL21; meta-analysis P = 1.3 x 10(-14), odds ratio = 0.63), suggesting that genetic variation in this region predisposes to celiac disease. 相似文献
273.
Association scan of 14,500 nonsynonymous SNPs in four diseases identifies autoimmunity variants 总被引:2,自引:0,他引:2
Wellcome Trust Case Control Consortium;Australo-Anglo-American Spondylitis Consortium 《Nature genetics》2007,39(11):1329-1337
We have genotyped 14,436 nonsynonymous SNPs (nsSNPs) and 897 major histocompatibility complex (MHC) tag SNPs from 1,000 independent cases of ankylosing spondylitis (AS), autoimmune thyroid disease (AITD), multiple sclerosis (MS) and breast cancer (BC). Comparing these data against a common control dataset derived from 1,500 randomly selected healthy British individuals, we report initial association and independent replication in a North American sample of two new loci related to ankylosing spondylitis, ARTS1 and IL23R, and confirmation of the previously reported association of AITD with TSHR and FCRL3. These findings, enabled in part by increased statistical power resulting from the expansion of the control reference group to include individuals from the other disease groups, highlight notable new possibilities for autoimmune regulation and suggest that IL23R may be a common susceptibility factor for the major 'seronegative' diseases. 相似文献
274.
Maller JB Fagerness JA Reynolds RC Neale BM Daly MJ Seddon JM 《Nature genetics》2007,39(10):1200-1201
The association of variants in complement factors H and B with age-related macular degeneration has led to more intense genetic and functional analysis of the complement pathway. We identify a nonsynonymous coding change in complement factor 3 that is strongly associated with risk of age-related macular degeneration in a large case-control sample. 相似文献
275.
MacArthur DG Seto JT Raftery JM Quinlan KG Huttley GA Hook JW Lemckert FA Kee AJ Edwards MR Berman Y Hardeman EC Gunning PW Easteal S Yang N North KN 《Nature genetics》2007,39(10):1261-1265
More than a billion humans worldwide are predicted to be completely deficient in the fast skeletal muscle fiber protein alpha-actinin-3 owing to homozygosity for a premature stop codon polymorphism, R577X, in the ACTN3 gene. The R577X polymorphism is associated with elite athlete status and human muscle performance, suggesting that alpha-actinin-3 deficiency influences the function of fast muscle fibers. Here we show that loss of alpha-actinin-3 expression in a knockout mouse model results in a shift in muscle metabolism toward the more efficient aerobic pathway and an increase in intrinsic endurance performance. In addition, we demonstrate that the genomic region surrounding the 577X null allele shows low levels of genetic variation and recombination in individuals of European and East Asian descent, consistent with strong, recent positive selection. We propose that the 577X allele has been positively selected in some human populations owing to its effect on skeletal muscle metabolism. 相似文献
276.
A single positively selected West Nile viral mutation confers increased virogenesis in American crows 总被引:1,自引:0,他引:1
Brault AC Huang CY Langevin SA Kinney RM Bowen RA Ramey WN Panella NA Holmes EC Powers AM Miller BR 《Nature genetics》2007,39(9):1162-1166
West Nile virus (WNV), first recognized in North America in 1999, has been responsible for the largest arboviral epiornitic and epidemic of human encephalitis in recorded history. Despite the well-described epidemiological patterns of WNV in North America, the basis for the emergence of WNV-associated avian pathology, particularly in the American crow (AMCR) sentinel species, and the large scale of the North American epidemic and epiornitic is uncertain. We report here that the introduction of a T249P amino acid substitution in the NS3 helicase (found in North American WNV) in a low-virulence strain was sufficient to generate a phenotype highly virulent to AMCRs. Furthermore, comparative sequence analyses of full-length WNV genomes demonstrated that the same site (NS3-249) was subject to adaptive evolution. These phenotypic and evolutionary results provide compelling evidence for the positive selection of a mutation encoding increased viremia potential and virulence in the AMCR sentinel bird species. 相似文献
277.
Gout AM;ADPKD Gene Variant Consortium Ravine D Harris PC Rossetti S Peters D Breuning M Henske EP Koizumi A Inoue S Shimizu Y Thongnoppakhun W Yenchitsomanus PT Deltas C Sandford R Torra R Turco AE Jeffery S Fontes M Somlo S Furu LM Smulders YM Mercier B Ferec C Burtey S Pei Y Kalaydjieva L Bogdanova N McCluskey M Geon LJ Wouters CH Reiterova J Stekrová J San Millan JL Aguiari G Del Senno L 《Nature genetics》2007,39(4):427-428
278.
Albert-Weissenberger C Cazalet C Buchrieser C 《Cellular and molecular life sciences : CMLS》2007,64(4):432-448
The bacterial pathogen Legionella pneumophila is found ubiquitously in fresh water environments where it replicates within protozoan hosts. When inhaled by humans it can
replicate within alveolar macrophages and cause a severe pneumonia, Legionnaires disease. Yet much needs to be learned regarding
the mechanisms that allow Legionella to modulate host functions to its advantage and the regulatory network governing its intracellular life cycle. The establishment
and publication of the complete genome sequences of three clinical L. pneumophila isolates paved the way for major breakthroughs in understanding the biology of L. pneumophila. Based on sequence analysis many new putative virulence factors have been identified foremost among them eukaryotic-like
proteins that may be implicated in many different steps of the Legionella life cycle. This review summarizes what is currently known about regulation of the Legionella life cycle and gives insight in the Legionella-specific features as deduced from genome analysis.
Received 1 September 2006; received after revision 10 October 2006; accepted 22 November 2006 相似文献
279.
280.
Infection of bacteria triggers innate immune defense reactions in Drosophila. So far, the only bacterial component known to be recognized by the insect innate immune system is peptidoglycan, one of
the most abundant constituents of the bacterial cell wall. Insects use peptidoglycan recognition proteins to detect peptidoglycan
and to activate innate immune responses. Such specialized peptidoglycan receptors appear to have evolved from phage enzymes
that hydrolyze bacterial cell walls. They are able to bind specific peptidoglycan molecules with distinct chemical moieties
and activate innate immune pathways by interacting with other signaling proteins. Recent X-ray crystallographic studies of
the peptidoglycan recognition proteins LCa, and LCx bound to peptidoglycan have provided structural insights into recognition
of peptidoglycan and activation of innate immunity in insects.
Received 28 December 2006; received after revision 2 February 2007; accepted 21 February 2007 相似文献