title: Mig-14 plays an important role in influencing gene expression of Salmonella enterica serovar Typhi, which contributes to cell invasion under hyperosmotic conditions.
abstract: mig-14 is a horizontally acquired host-induced virulence gene in Salmonella enterica serovar Typhi. The molecular function of mig-14 is still unknown; sequence analysis showed that mig-14 shared homology with the helix-loop-helix motif of the AraC family of transcriptional regulatory proteins. In our previous microarray-based studies, mig-14 was upregulated at the early stage of high osmotic stress, indicating a potential role under this condition. Therefore, we compared growth and the global transcriptional difference between wild-type and mig-14 mutant strains to identify the role of Mig-14. The results showed that growth of mig-14 mutant strain was clearly slower than that of the wild-type strain, and 148 genes showed significant differences in expression between these two strains under upshift high osmotic treatment for 30 min. In total, 77 genes and 71 genes in the mig-14 mutant strain were upregulated and downregulated, respectively. Genes involved in invasion, virulence, flagellation, motility and chemotaxis of Salmonella were downregulated. Thus, cell invasion abilities of these two strains were further analyzed. The results confirmed that activities of mig-14 were important for cell invasion.
authors.affiliation: Department of Biochemistry and Molecular Biology, Jiangsu University School of Medical Technology, Zhenjiang, Jiangsu 212013, China. Electronic address: shengxiumei@hotmail.com.
authors.forename: Xiumei
authors.initials: X
authors.lastname: Sheng
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Qiufeng
authors.initials: Q
authors.lastname: Xia
authors.forename: Shungao
authors.initials: S
authors.lastname: Xu
authors.forename: Huaxi
authors.initials: H
authors.lastname: Xu
authors.forename: Xinxiang
authors.initials: X
authors.lastname: Huang
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004705:Endocytosis; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D009997:Osmotic Pressure; D012485:Salmonella typhi / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D037521:Virulence Factors
keywords: Cell invasion; Regulation of gene expression; Salmonella enterica serovar Typhi; mig-14