副溶血弧菌是引发微生物食物中毒的首要病原菌，H-NS为一个全局性的转录因子，负调控大量靶基因，但其在副溶血性弧菌致病性调控中的功能和意义还缺乏研究。本研究在系统分析野生株、hns突变株、回补株的小鼠致死活性、细胞毒性、肠毒性和溶血活性等毒力表型的基础上，用RNAseq技术进行野生株和hns突变株的比较转录分析，结合生物信息学预测，筛选可能受H-NS直接调控的靶基因，进而用实时定量RT-PCR和凝胶阻滞实验，鉴定H-NS直接调控的靶基因，这些靶基因组成H-NS调控元，从而证实副溶血弧菌H-NS是整体调控子，控制众多细胞途径。进而采用LacZ报告基因融合、引物延伸、DNA酶I足迹等实验技术，深入研究H-NS直接调控关键毒力基因的精细机制。最终将表型和基因调控实验数据结合起来，确定H-NS是如何通过调控关键毒力来实现对副溶血弧菌致病性的调控。本研究的完成将促进我们对副溶血弧菌致病机制理论的认识。

The regulation of pathogenicity by the H-NS regulator in Vibrio parahaemolyticus is poorly understood. In this study, the lethality against mice, cytotoxicity, enterotoxicity, and hemolytic activity will be systematically characterized for the wild-type, hns mutant, and complemented mutant strains of pandemic V. parahaemolyticus. The RNAseq-based comparative transciptomics assay in combination with the bioinformatics analysis will be performed for the wild-type and hns mutant strains to identify the H-NS-dependent genes in a genome-wide manner. The real-time quantitative RT-PCR and gel mobility shift assays will be then carried out to identify the directly H-NS targets that constitute the H-NS regulon. Subsequently, the fine mechanisms used by H-NS to regulate key virulence genes will be characterized by combined use of the LacZ fusion reporter, primer extension, and DNase I footprinting technologies. The final dataset will promote us to gain a deeper understanding of regulation of V. parahaemolyticus pathogenicity by H-NS.