Hfq is essential for Vibrio cholerae virulence and downregulates sigma expression.
Hfq is essential for Vibrio cholerae virulence and downregulates sigma expression.
复制标题
DOI：
--
复制
发表时间：
2004
影响因子：
3.6
通讯作者：
Yanpeng Ding;B. M. Davis;M. Waldor
中科院分区：
文献类型：
--
作者：
Yanpeng Ding;B. M. Davis;M. Waldor
HFq是一种RNA结合蛋白，可与小的非翻译RNA（sRNA）和mRNA相互作用，以调节转录后基因表达。在大肠杆菌和鼠伤寒沙门氏菌中，Hfq是有效表达稳定相σ因子σ（S）所必需的，因此对沙门氏菌的毒力至关重要。我们已经发现Hfq对于霍乱弧菌的毒力也是必不可少的，因为缺乏Hfq的菌株不能在乳鼠肠道定殖。霍乱弧菌hfq的缺失不会阻止sigma（S）的产生，也不会阻止TCP（霍乱弧菌的主要定植因子）的表达。替代性σ因子σ（E）的表达和活性在霍乱弧菌hfq突变体中显著增加。将hfq突变体的转录组与也过表达sigma（E）的rseA突变体的转录组进行比较，发现sigma（E）控制了hfq突变体中被发现上调的基因的大约一半。然而，增加的σ（E）似乎不能解释该菌株的毒力降低。sRNA与Hfq结合可能是霍乱弧菌致病性的关键调节因子。
Hfq is an RNA-binding protein that interacts with both small untranslated RNAs (sRNAs) and mRNAs to modulate gene expression post-transcriptionally. In Escherichia coli and Salmonella typhimurium, Hfq is required for efficient expression of the stationary phase sigma factor sigma(S), and consequently is critical for Salmonella virulence. We have found that Hfq is also essential for the virulence of Vibrio cholerae, as strains lacking hfq fail to colonize the suckling mouse intestine. Deletion of the V. cholerae hfq does not prevent production of sigma(S), nor does it prevent expression of TCP, V. cholerae's primary colonization factor. The expression and activity of the alternative sigma factor sigma(E) are dramatically increased in a V. cholerae hfq mutant. Comparison of the transcriptome of an hfq mutant with that of an rseA mutant, which also overexpresses sigma(E), revealed that sigma(E) controls approximately half the genes found to be upregulated in the hfq mutant. However, increased sigma(E) does not appear to account for this strain's reduced virulence. It is likely that sRNAs, in conjunction with Hfq, are critical regulators of V. cholerae pathogenicity.