Mechanistic Studies of the Type I CRISPR-Cas System

项目摘要 最近发现原核生物可以获得对病毒和质粒的抗性 通过将外源DNA的短片段整合到规则间隔的短片段簇中， 回文重复序列（CRISPR）。然后这些重复被转录并加工成小的 引导RNA用于指导外源核酸的破坏。这一机制 与真核RNA干扰有许多相似之处，但与RNA干扰相关的蛋白质 CRISPR反应与它们的真核对应物在进化上无关。我们的长期 我们的目标是了解CRISPR介导的耐药性的生物化学和结构基础， 原核生物。这里的目的是确定效应蛋白， 负责最终摧毁外国侵略者，是专门招募外国 DNA.我们的目标将结合联合收割机生化，结构和细胞为基础的实验。成功 完成拟议的研究是重要的，因为它将增加我们对 细菌对病毒和质粒的抗性。这两个基因因素都起着重要的作用 在致病菌遗传学中的作用。

Project Summary It has recently been discovered that prokaryotes can acquire resistance to viruses and plasmids by integrating short fragments of foreign DNA into clusters of regularly interspaced short palindromic repeats (CRISPR's). These repeats are then transcribed and processed into small guide RNA's that are used to direct the destruction of foreign nucleic acid. This mechanism has many parallels with eukaryotic RNA interference but the proteins that are associated with the CRISPR response are evolutionarily unrelated to their eukaryotic counterparts. Our long-term goal is to understand the biochemical and structural basis of CRISPR-mediated resistance in prokaryotes. The objective here is to determine the mechanism by which an effector protein, responsible for the ultimate destruction of the foreign invader, is recruited specifically to foreign DNA. Our objective will combine biochemical, structural and cell based experiments. Successful completion of the proposed studies is significant because it will increase our understanding of bacterial resistance to viruses and plasmids. Both of these genetic elements play important roles in the genetics of pathogenic bacteria.