Role of Hfq in Vibrio cholerae virulence

Hfq 在霍乱弧菌毒力中的作用

基本信息

批准号：
6765751
负责人：
Matthew K WALDOR
金额：
$ 31.7万
依托单位：
TUFTS UNIVERSITY BOSTON
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-04-01 至 2006-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6765751
关键词：
RNA binding protein Vibrio cholerae bacterial RNA bacterial cytopathogenic effect bacterial genetics bacterial proteins gene expression genetic regulation genetic regulatory element laboratory mouse microarray technology molecular cloning nucleic acid purification protein protein interaction protein structure function virulence

项目摘要

DESCRIPTION (provided by applicant): Vibrio cholerae causes the severe diarrheal disease cholera. We found that Hfq, an RNA-binding protein, is essential for Vibrio cholerae virulence. Deletion of hfq abolished V. cholerae colonization of the suckling mouse intestine, but had a minimal effect on growth in vitro and did not influence expression of known colonization factors. Thus, Hfq appears to control previously undescribed pathways essential for cholera pathogenesis. In E. coli, Hfq binds to numerous small untranslated RNAs (sRNAs), modulates their activities, and thereby controls expression of a wide variety of genes. Hfq also binds to some mRNAs in E. coli and alters gene expression directly. Although Hfq in V. cholerae probably acts by similar mechanisms, the distinct phenotypes of hfq V. cholerae and E. coli suggest that the proteins bind different sets of RNAs and control distinct regulons. No RNAs bound by V. cholerae Hfq and no V. cholerae sRNAs have been characterized to date. The goals of this R21 application are to identify pathways controlled by Hfq in V. cholerae, particularly Hfq-regulated genes that contribute to V. cholerae virulence, and to characterize the mechanisms controlling their expression. Experiments in Aim I - to define the Hfq regulon - will generate the first knowledge of Hfq-regulated effectors in V. cholerae. Experiments in Aim II - cloning of sRNAs and mRNAs that interact with Hfq - will utilize a new, unbiased approach for cloning interacting RNAs. Experiments in both Aims I and II will explore which of Hfq's interaction partners and downstream effectors contribute to V. cholerae virulence and thus illuminate currently unknown mediators of pathogenesis. Experiments in Aim III - to match sRNAs to the genes they regulate and characterize processes of Hfq dependent gene regulation - will create the foundation for detailed analyses of the mechanisms by which Hfq controls gene expression in V. cholerae. These studies will also facilitate disruption of Hfq-mediated pathways. As Hfq contributes to the virulence of several other Class B Priority Pathogens in addition to V. cholerae, Hfq or its downstream effectors may prove to be valuable targets for new antimicrobial agents.

描述（由申请人提供）：霍乱弧菌引起严重的腹泻病霍乱。我们发现 Hfq（一种 RNA 结合蛋白）对于霍乱弧菌毒力至关重要。 hfq的缺失消除了霍乱弧菌在乳鼠肠道的定植，但对体外生长的影响很小，并且不影响已知定植因子的表达。因此，Hfq 似乎控制着先前未描述的霍乱发病机制所必需的途径。在大肠杆菌中，Hfq 与许多小非翻译 RNA (sRNA) 结合，调节它们的活性，从而控制多种基因的表达。 Hfq 还与大肠杆菌中的一些 mRNA 结合并直接改变基因表达。尽管霍乱弧菌中的 Hfq 可能通过相似的机制发挥作用，但 hfq 霍乱弧菌和大肠杆菌的不同表型表明这些蛋白质结合不同组的 RNA 并控制不同的调节子。迄今为止，尚未对霍乱弧菌 Hfq 结合的 RNA 和霍乱弧菌 sRNA 进行表征。 R21 应用的目标是确定霍乱弧菌中 Hfq 控制的途径，特别是导致霍乱弧菌毒力的 Hfq 调节基因，并表征控制其表达的机制。目标 I 中的实验——定义 Hfq 调节子——将产生霍乱弧菌中 Hfq 调节效应子的第一个知识。 Aim II 中的实验——克隆与 Hfq 相互作用的 sRNA 和 mRNA——将利用一种新的、公正的方法来克隆相互作用的 RNA。目标 I 和 II 中的实验将探索哪些 Hfq 相互作用伙伴和下游效应器对霍乱弧菌毒力有贡献，从而阐明目前未知的发病机制介质。 Aim III 中的实验 - 将 sRNA 与其调节的基因相匹配并表征 Hfq 依赖性基因调节过程 - 将为详细分析 Hfq 控制霍乱弧菌基因表达的机制奠定基础。这些研究还将促进 Hfq 介导途径的破坏。由于除了霍乱弧菌之外，Hfq 还对其他几种 B 类优先病原体的毒力产生影响，因此 Hfq 或其下游效应子可能被证明是新抗菌药物的有价值的靶点。