Phage-induced modifications of RNA polymerase

噬菌体诱导的 RNA 聚合酶修饰

基本信息

批准号：
7933443
负责人：
KONSTANTIN V SEVERINOV
金额：
$ 25.75万
依托单位：
RUTGERS, THE STATE UNIV OF N.J.
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-09-30 至 2010-08-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Our long-term goal is to understand the function and regulation of cellular RNA polymerase (RNAP) in molecular detail. Bacteriophages evolved elaborate mechanisms to regulate transcription of bacterial host to serve viral needs. The number of phage-encoded transcription regulators exceeds the number of bacterial regulators by orders of magnitude. Phage regulatory systems are usually compact, robust and efficient. Studies of a handful of phage-induced modifications of host RNAP provided important paradigms of regulation of gene expression that are applicable to bacteria and higher organisms. The goal of this research is to study phage-induced modifications of bacterial host RNAP and the role of these modifications in viral development. In vitro, RNAP sites that are targeted by phage regulators will be identified and the mechanisms of action of phage regulators will be determined. In vivo, genetic and genomic approaches will be used to understand the biological consequences of RNAP modifications by phage-encoded inhibitors. The following model systems will be analyzed: The T4 phage. Molecular mechanism of termination factor Ale will be studied. The mechanism of negative regulation of host and early viral genes and positive regulation of middle viral genes by T4 AsiA will be determined. The role of ADP-ribosylation of RNAP alpha in regulation of early and middle viral transcription will be studied. The T7 phage. The role of RNAP beta phosphorylation by T7 gp0.7, the molecular mechanism of E. coli RNAP transcription inhibition by T7 gp2, and the role of gp2 in viral DNA packaging will be investigated. The Sp6 phage. Sp6-encoded inhibitor(s) of S. typhimurium RNAP will be purified and characterized. The Xp10 phage. Molecular mechanism of a novel Xp 10-encoded antitermination factor p7 will be identified. Global transcription profiling will be used to better understand gene expression strategy of Xp10, a highly unusual phage that appears to combine the regulatory paradigms of well-studied T7 and lambda phages. The thematic unity of this application stems from its focus on negative regulation of bacterial RNAP by covalent modifications or RNAP-interacting proteins during viral development. Studies of phage-encoded proteins and modifications of host RNAP will lead to deeper understanding of viral biology. On the other hand, phage-encoded transcription inhibitors will be used as molecular probes to better understand RNAP mechanism and regulation and to uncover RNAP sites that can be targets for drug design.

描述（由申请人提供）：我们的长期目标是通过分子细节了解细胞RNA聚合酶（RNAP）的功能和调节。噬菌体发展了精心的机制，以调节细菌宿主的转录以满足病毒需求。通过数量级，噬菌体编码的转录调节剂的数量超过了细菌调节剂的数量。噬菌体调节系统通常紧凑，稳健且有效。对少数噬菌体诱导的宿主RNAP修饰的研究提供了适用于细菌和较高生物体的基因表达调节的重要范式。这项研究的目的是研究噬菌体诱导的细菌宿主RNAP的修饰以及这些修饰在病毒发育中的作用。将确定由噬菌体调节器靶向的RNAP位点，并将确定噬菌体调节剂的作用机理。在体内，遗传和基因组方法将用于了解通过噬菌体编码的抑制剂对RNAP修饰的生物学后果。将分析以下模型系统： T4噬菌体。将研究终止因子ALE的分子机理。将确定宿主和早期病毒基因的负调控的机制以及T4亚洲对中间病毒基因的阳性调节。将研究RNAPα的ADP-核糖基化在调节早期和中期病毒转录中的作用。 T7噬菌体。 T7 GP0.7的RNAPβ磷酸化，T7 GP2抑制大肠杆菌RNAP转录的分子机制以及GP2在病毒DNA包装中的作用。 SP6噬菌体。鼠伤寒链球菌RNAP的SP6编码抑制剂将被纯化和表征。 XP10噬菌体。将确定新型XP 10代码抗灭菌因子P7的分子机制。全球转录分析将用于更好地了解XP10的基因表达策略，XP10是一种非常不寻常的噬菌体，似乎结合了研究良好的T7和Lambda噬菌体的调节范式。该应用的主题统一性源于其在病毒发育过程中通过共价修饰或RNAP相互作用蛋白对细菌RNAP负调控的重点。噬菌体编码蛋白和宿主RNAP修饰的研究将使人们对病毒生物学的更深入了解。另一方面，噬菌体编码的转录抑制剂将被用作分子探针，以更好地理解RNAP机制和调节，并发现可以成为药物设计靶标的RNAP位点。