Characterization of a novel ETEC virulence regulator

描述（由申请人提供）： 基因调控在致病菌的毒力中起着至关重要的作用。我们的长期目标是了解转录因子（TF）如何调节致病性大肠杆菌（ETEC）的毒力过程。ETEC是发展中国家腹泻的主要细菌原因，每年导致> 300，000人死亡，主要是儿童。在ETEC中已鉴定出许多毒力基因，但对这些基因的调控知之甚少。我们最近已经确定了TF，RoaA，编码的ETEC毒力质粒之一，这是必需的有效粘附肠上皮细胞。我们假设RoaA是ETEC毒力的关键调节因子。该提案的目标是通过核苷酸分辨率全面鉴定RoaA的调控靶点。我们将使用互补的基因组方法ChIP-seq和RNA-seq来识别直接和间接的调节靶点。我们将确定ETEC毒力所需的靶基因。然后，我们将使用遗传和生化分析来确定RoaA在这些基因启动子上的精确DNA位点。本研究为深入了解ETEC毒力基因的调控机制提供了重要的理论依据，也为今后ETEC毒力的研究奠定了基础。 公共卫生相关性： 产肠毒素大肠杆菌（ETEC）每年导致30多万人死亡。我们已经确定了一种ETEC调节蛋白，该蛋白是有效附着于人肠道上皮细胞所必需的。我们将确定这种蛋白质的调控靶点。

DESCRIPTION (provided by applicant): Gene regulation plays a critical role in the virulence of pathogenic bacteria. Our long-term goal is to understand how transcription factors (TFs) regulate virulence processes in the pathogenic species, Enterotoxigenic Escherichia coli (ETEC). ETEC is the leading bacterial cause of diarrhea in the developing world and causes >300,000 deaths annually, mainly in children. Many virulence genes have been identified in ETEC but relatively little is known about regulation of these genes. We have recently identified a TF, RoaA, encoded on one of the ETEC virulence plasmids, that is required for efficient adhesion to gut epithelial cells. We hypothesize that RoaA is a key regulator of ETEC virulence. The goal of this proposal is to comprehensively identify the regulatory targets of RoaA with nucleotide resolution. We will use complementary genomic approaches, ChIP-seq and RNA-seq, to identify direct and indirect regulatory targets. We will determine which of the target genes are required for ETEC virulence. We will then use genetic and biochemical analyses to identify the precise DNA sites for RoaA at the promoters of these genes. The proposed work will provide important insight into the regulation of ETEC virulence genes, and will form the foundation of future studies of ETEC virulence. PUBLIC HEALTH RELEVANCE: NARRATIVE Enterotoxigenic Escherichia coli (ETEC) kills more than 300,000 people annually. We have identified an ETEC regulatory protein that is required for efficient attachment to human gut epithelial cells. We will identify the regulatory targets of this protein.