FimX in Regulation of Type IV Pili Expression

描述（由申请人提供）：FimX是铜绿假单胞菌（PA）中最近描述的一种蛋白质，显示可调节IV型丸剂（TFP），一种重要的毒力因子，以响应环境信号。我们建议FimX，GGDEF/EAL包含蛋白质，在TFP组装的作用的特点。我们将证实，FimX合成环二GMP（c-diGMP），一种调节分子，假设是重要的各种细胞功能。将阐明每个FimX结构域对c-diGMP调节的贡献。我们已经确定了两个组件的ABC转运伙伴与FimX在酵母双杂交筛选。我们将通过免疫共沉淀研究确认这些相互作用，并确定结合这些蛋白质所需的FimX结构域。此外，我们将产生缺乏这些ABC转运蛋白的PA菌株，并确认它们在TFP调节中的作用。进一步的研究将确定这些运输者是出口商还是进口商。这些研究将确定c-diGMP是否是调节PA抽搐运动的第二信使。我们还将描述第一个ABC转运蛋白在PA参与控制TFP的表达。

DESCRIPTION (provided by applicant): FimX is a recently described protein in Pseudomonas aeruginosa (PA) shown to regulate type IV pill (TFP), an important virulence factor, in response to environmental signals. We propose to characterize the role of FimX, a GGDEF/EAL containing protein, in TFP assembly. We will confirm that FimX synthesizes cyclic di-GMP (c-diGMP), a regulatory molecule hypothesized to be important for a wide variety of cellular functions. The contributions of each FimX domain to regulation of c-diGMP will be elucidated. We have identified two components of ABC transporters that partner with FimX in a yeast two-hybrid screen. We will confirm these interactions with co-immunoprecipitation studies and identify the FimX domains required to bind these proteins. Furthermore, we will generate PA strains lacking these ABC transporters and confirm their role in the regulation of TFP. Additional studies will determine if these transporters are exporters or importers. These studies will determine whether c-diGMP is a second messenger regulating twitching motility in PA. We also will characterize the first ABC transporters identified in PA involved in controlling TFP expression.