RUI: Role of VirC1 and VirC2 in Regulation of Substrate Delivery by the VirB/D4 Secretion Apparatus of Agrobacterium Tumefaciens

RUI：VirC1 和 VirC2 在调节根癌农杆菌 VirB/D4 分泌装置的底物递送中的作用

• 批准号: 0416471
• 负责人: Lois Banta
• 金额: $ 33万
• 依托单位: Williams College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-15 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0416471&HistoricalAwards=false
• 关键词: RUI; Role; VirC1; VirC2; Regulation

The soil bacterium Agrobacterium tumefaciens transports both proteins and DNA into a host plant cell, resulting in crown gall tumors ('plant cancer') at the infection site. The transport machinery, comprised of multiple VirB proteins and VirD4 working as a complex in the bacterial membrane to promote export of the DNA and proteins, is the prototype for several similar systems required for other medically significant bacteria to cause disease in their mammalian hosts. The goal of the project is to characterize two proteins, VirC1 and VirC2, that appear to enhance the efficiency of DNA delivery via this transport apparatus. This research will test the hypothesis that VirC1 and VirC2 interact to tether the source of the transferred DNA to specific sites on the bacterial cell membrane, thereby promoting DNA interactions with the VirB/VirD4 secretion machinery. Biochemical and microscopic approaches will be used to determine if VirC1 associates with components of the transport complex. The influence of host cell contact on these interactions will be investigated. Biochemical and genetic approaches will be used to probe for interactions between VirC1 and VirC2. The data obtained will also reveal where VirC2 is located within the cell, and whether a specific region of the VirC1 protein is essential for VirC1's functions. The results will provide novel information about two poorly characterized virulence proteins and, more broadly, the regulation of trafficking through an important model secretion system. Agrobacterium tumefaciens is widely used to introduce new genes into plants, but its utility is limited by the fact that some plants, including many agriculturally important grains, are poor hosts. These investigations into the roles played by VirC may well have significant implications for the genetic modification of hitherto non-host species, and hence for global food productivity. The project will be used to provide undergraduates in opportunities to do research.

土壤细菌根癌农杆菌将蛋白质和DNA输送到宿主植物细胞中，导致感染部位的冠瘤(植物癌)。运输机制由多个VIRB蛋白和VirD4组成，作为细菌膜上的复合体，促进DNA和蛋白质的出口，是其他医学上重要的细菌在哺乳动物宿主中致病所需的几个类似系统的原型。该项目的目标是表征两种蛋白质，VirC1和VirC2，这两种蛋白质似乎可以通过这种运输装置提高DNA输送的效率。这项研究将检验这样一种假设，即VirC1和VirC2相互作用，将转移的DNA来源拴在细菌细胞膜上的特定位置，从而促进DNA与VIRB/VirD4分泌机制的相互作用。将使用生化和显微方法来确定Virc1是否与运输复合体的组件相关联。宿主细胞接触对这些相互作用的影响将被调查。将使用生化和遗传方法来探索VirC1和VirC2之间的相互作用。获得的数据还将揭示病毒C2在细胞内的位置，以及病毒C 1蛋白的特定区域是否对病毒C 1‘S的功能是必需的。这些结果将提供关于两种特性不佳的毒力蛋白的新信息，更广泛地说，通过一个重要的模型分泌系统来调节运输。农杆菌被广泛用于将新基因导入植物，但由于一些植物，包括许多农业上重要的谷物，是糟糕的宿主，其应用受到限制。这些对ViRC所起作用的研究很可能会对迄今非寄主物种的基因改造产生重大影响，从而对全球粮食生产力产生重大影响。该项目将用于为本科生提供做研究的机会。