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排序方式: 共有2234条查询结果,搜索用时 31 毫秒
921.
922.
C. S. Tang Y. Sribudiani X. P. Miao A. R. de Vries G. Burzynski M. T. So Y. Y. Leon B. H. Yip J. Osinga K. J. W. S. Hui J. B. G. M. Verheij S. S. Cherny P. K. H. Tam P. C. Sham R. M. W. Hofstra M. M. Garcia-Barceló 《Human genetics》2010,127(6):675-683
Hirschsprung’s disease (HSCR) is a congenital disorder characterised by the absence of ganglia along variable lengths of the intestine. The RET gene is the major HSCR gene. Reduced penetrance of RET mutations and phenotypic variability suggest the involvement of additional modifying genes in the disease. A RET-dependent modifier locus was mapped to 9q31 in families bearing no coding sequence (CDS) RET mutations. Yet, the 9q31 causative locus is to be identified. To fine-map the 9q31 region, we genotyped 301 tag-SNPs spanning 7 Mb on 137 HSCR Dutch trios. This revealed two HSCR-associated regions that were further investigated in 173 Chinese HSCR patients and 436 controls using the genotype data obtained from a genome-wide association study recently conducted. Within one of the two identified regions SVEP1 SNPs were found associated with Dutch HSCR patients in the absence of RET mutations. This ratifies the reported linkage to the 9q31 region in HSCR families with no RET CDS mutations. However, this finding could not be replicated. In Chinese, HSCR was found associated with IKBKAP. In contrast, this association was stronger in patients carrying RET CDS mutations with p = 5.10 × 10?6 [OR = 3.32 (1.99, 5.59)] after replication. The HSCR-association found for IKBKAP in Chinese suggests population specificity and implies that RET mutation carriers may have an additional risk. Our finding is supported by the role of IKBKAP in the development of the nervous system. 相似文献
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924.
Sae-Yeon Hong Jinny So Jungkwan Lee Kyunghun Min Hokyoung Son Chanju Park Sung-Hwan Yun Yin-Won Lee 《Fungal genetics and biology : FG & B》2010,47(4):364-372
We identified two syntaxin-like SNARE genes, named GzSYN1 and GzSYN2, from the plant pathogenic ascomycete Gibberella zeae, and characterized the functions and cellular localization of these genes. The GzSYN1 deletion mutant (Δgzsyn1) had 71% reduced hyphal growth compared to the wild-type strain, but produced perithecia with normal ascospores. Δgzsyn2 had the same hyphal growth rate as the wild-type, but completely lost both self and female fertility. When Δgzsyn2 was spermatized for Δmat1-1 or Δmat1-2 strains, it retained its male fertility, but the ascus shape was abnormal and ascospore delimitation was delayed. The Δgzsyn1 and Δgzsyn2 virulence on barley was reduced by 67% and 75%, respectively, compared to the wild-type. The GFP::GzSYN1 fusion protein was localized in vesicles, vacuoles, plasma membranes, and septa, whereas GFP::GzSYN2 was found only in plasma membranes and septa. These results suggest that syntaxins have key roles in fungal development and virulence in G. zeae. 相似文献
925.
Y.‐W. Lee S.‐Y. Jeong Y.‐H. In K.‐Y. Kim J.‐S. So W.‐S. Chang 《Letters in applied microbiology》2010,50(5):452-456
Aims: To reveal the effects of the O‐polysaccharide antigen of Bradyrhizobium japonicum LPS on biofilm formation and motility. Methods and Results: Wild type and O‐antigen‐deficient mutant strains of B. japonicum were tested for biofilm formation on polyvinyl chloride (PVC) surfaces and motility on semi‐solid (0·3%) agar media. After 7 days of incubation, the amount of biofilms formed by the mutant was c. 3·5‐fold greater than that of the wild type. Unlike biofilm formation, the motility assay revealed that the mutant strain was less motile than the wild type. Conclusions: This study shows enhanced biofilm formation and decreased motility by the O‐antigen‐deficient mutant, suggesting that the lack of the O‐polysaccharide of the rhizobial LPS is associated with biofilm‐forming ability and movement. Significance and Impact of the Study: LPS plays an important role in both pathogenic and beneficial bacteria. It has also been reported that LPS deficiency negatively affects biofilm formation. However, our results demonstrate that the O‐antigen‐deficient mutant enhances biofilm formation, presumably through a significant increase in hydrophobicity. It is notable that the hydrophobicity of cell walls might be a key regulator in controlling biofilm development in B. japonicum. 相似文献
926.
Pradeep Reddy Marri Mary Paniscus Nathan J. Weyand María A. Rendón Christine M. Calton Diana R. Hernández Dustin L. Higashi Erica Sodergren George M. Weinstock Steven D. Rounsley Magdalene So 《PloS one》2010,5(7)
Commensal bacteria comprise a large part of the microbial world, playing important roles in human development, health and disease. However, little is known about the genomic content of commensals or how related they are to their pathogenic counterparts. The genus Neisseria, containing both commensal and pathogenic species, provides an excellent opportunity to study these issues. We undertook a comprehensive sequencing and analysis of human commensal and pathogenic Neisseria genomes. Commensals have an extensive repertoire of virulence alleles, a large fraction of which has been exchanged among Neisseria species. Commensals also have the genetic capacity to donate DNA to, and take up DNA from, other Neisseria. Our findings strongly suggest that commensal Neisseria serve as reservoirs of virulence alleles, and that they engage extensively in genetic exchange. 相似文献
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928.
929.