AphB互作蛋白的筛选及其对霍乱弧菌毒力因子调控机制研究

项目名称： AphB互作蛋白的筛选及其对霍乱弧菌毒力因子调控机制研究

项目编号： No.81501724

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 樊粉霞

作者单位： 中国疾病预防控制中心传染病预防控制所

项目金额： 18万元

中文摘要： 产毒霍乱弧菌是导致霍乱的病原体，目前仍在全球流行，并引起O139霍乱这一新发传染病。产毒霍乱弧菌主要的致病因子包括霍乱毒素CT和菌毛TCP，这些毒力因子表达受到多个蛋白的级联调控：毒力基因直接被ToxT激活，toxT基因又受到ToxR和TcpP的协同调控，其中tcpP的转录表达又受到AphA和AphB的联合正向调控。在霍乱弧菌环境生存和感染过程中，AphB作为主要调控蛋白，能够感知微环境信号的变化，发挥毒力基因的激活作用。然而哪些蛋白与 AphB直接互作协同发挥毒力调控作用还不清楚。基于我们的前期研究工作,本研究拟通过扩展霍乱弧菌基因文库，利用BACTH进一步筛选与AphB互作的蛋白，通过对初筛蛋白验证及分析其对毒力调控通路下游基因转录、表达的影响，明确蛋白互作以及感受外界信号调节毒力表达的机制。本研究将扩展我们对调控蛋白AphB的认识，完善毒力调控通路，为揭示霍乱弧菌致病性提供分子依据。

中文关键词： 霍乱弧菌；；BACTH；；AphB；；蛋白互作；调控

英文摘要： Toxigenic Vibrio cholerae can cause human acute diarrhea – cholera, O139 cholera as an emerging infectious diseases is still epidemic globally. Toxigenic Vibrio cholerae expresses two major virulence factors including cholera toxin CT encoded by ctxAB and pili TCP encoded by tcpA, which are stepwise regulated by more than a regulatory protein. ToxT as a regulatory protein directly activates the expression of tcpA and ctxAB, two membrane proteins ToxR and TcpP coordinately promote the transcription of toxT. In Vibrio cholerae environmental survival and infection process, AphB as a major regulator can activate the transcription of tcpP by binding its promoter and ultimately causes disease. However, it is still unclear which protein can interact with AphB directly to regulate virulence genes. Based on our preliminary studies, in this research, we try to further screen some proteins, which can directly interact with AphB, from the Vibrio cholerae genomic library. We will confirm their interaction and analyze their influence on the transcription and expression of the virulence genes in the virulence regulatory pathway. How these proteins interact and sense micro-environmental signals to regulate the virulence gene expression will be further analyzed. This study will expand our understanding on the regulation mechanism of AphB. The virulence regulatory pathway will be further refined and supplemented. This study will provide us molecular basis for revealing the pathogenesis of Vibrio cholerae.

英文关键词： Vibrio cholerae;BACTH ;AphB ;protein interaction;regulation