Hfq对溶藻弧菌碱性丝氨酸蛋白酶合成的调控机制研究

项目名称： Hfq对溶藻弧菌碱性丝氨酸蛋白酶合成的调控机制研究

项目编号： No.31301059

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： 刘欢

作者单位： 陕西科技大学

项目金额： 23万元

中文摘要： 溶藻弧菌是我国南方水产养殖重要病原菌，主要毒力因子为胞外碱性丝氨酸蛋白酶，其合成受到群体感应系统的紧密调控。前期研究发现，溶藻弧菌中存在非编码小RNA（sRNA）伴侣蛋白Hfq，且Hfq在溶藻弧菌的多种生理活动中起重要调控作用，如碱性丝氨酸蛋白酶的活性及其他毒力相关表型。Hfq对碱性丝氨酸蛋白酶活性的调控主要通过转录后抑制群体感应系统中枢元件LuxR实现。本项目以Hfq对LuxR转录后调控作用为出发点，研究Hfq在溶藻弧菌中调控碱性丝氨酸蛋白酶合成的分子机制，包括鉴定参与Hfq调控碱性丝氨酸蛋白酶活性的相关sRNA及其对LuxR靶标mRNA分子稳定性的影响，阐明Hfq-sRNA-LuxR之间的作用机制，描绘Hfq-sRNA系统与群体感应系统之间的相互作用网络图景。揭示Hfq调控溶藻弧菌碱性丝氨酸蛋白酶活性的作用机制将为病原菌致病机制研究及海水养殖病害防治新技术的开发应用提供一定的理论依据。

中文关键词： Hfq；Qrr；群体感应；碱性丝氨酸蛋白酶；溶藻弧菌

英文摘要： Vibrio alginolyticus is the main pathogen causing serious economic loss annually in the aquaculture in South China and its major virulence factor is determined as the exotoxin, alkaline serine protease (Asp) which is under the tight regulation of quorum sensing system. Moreover, the previous work has characterized that the chaperon protein of non-coding small RNA, Hfq is present in V. alginolyticus and indicated that Hfq plays pivotal roles in the modulation of various progresses in this pathogen, such as the extracellular protease avtivity and many other virulence-related phynotypes. Hfq takes effects on the alkaline serine protease production mainly by the post-transcriptional inhibition of the core element in the quorum sensing system, LuxR. This study intends to figure out the underlying mechanisms of the regulation of Hfq on the Asp production in V. alginolyticus. It's going to characterize the sRNAs which are participating in the Asp activity and determine the effects of the sRNAs on the target mRNA stability. Besides, this study also attempts to reveal the roles of Hfq in the base-pairing process between the sRNA and the responding target mRNA and draw the interaction diagram between the Hfq-sRNA and the quorum sensing system in V. alginolyticus. The study will open a brand new frontier for the pathogenec

英文关键词： Hfq；Qrr；quorum sensing；Asp；Vibrio alginolyticus