MECHANISM AND REGULATION OF E COLI RNA POLYMERASE

大肠杆菌RNA聚合酶的机制和调控

• 批准号: 3278122
• 负责人: WILLIAM R MCCLURE
• 金额: $ 36.81万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-07-01 至 1995-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3278122
• 关键词: DNA directed RNA polymerase; Escherichia coli; RNA biosynthesis; bacterial RNA; bacterial genetics; cyclic AMP; cyclic nucleoside monophosphate; gene expression; gene induction /repression; gene mutation; genetic manipulation; genetic promoter element; genetic regulation; genetic transcription; transcription factor

This project is designed to investigate important questions about the mechanism and regulation of transcription initiation in Escherichia coli. The experiments are designed to provide a fundamental biochemical understanding of several complex phenomena involved in the recognition of E. coli promoters by RNA polymerase. A series of studies will characterize the "closed complex", an important reaction intermediate in the initiation process. Experiments performed in vitro will also characterize the properties of a mutant sigma subunit that displays altered promoter recognition in vivo. The effects of DNA supercoiling on promoter recognition will be explored using a newly-developed assay for topoisomer selectivity. This novel approach will be extended in a study of positive regulation by cap*cAMP at the lactose and galactose operon promoters. The modulation of promoter selectivity by the galactose repressor at the gal promoters will also be characterized. The structural determinants of RNA-RNA pairing will also be determined in an example of antisense RNA gene regulation. In this case the regulation occurs primarily at the translation initiation steps, however, the principles for RNA-RNA pairing that emerge will be applicable to many other steps in gene expression and its regulation. The answers to the questions we have posed will contribute to the biochemical description of the control of gene expression.

该项目旨在调查有关 大肠杆菌转录起始的机制和调控。 这些实验旨在提供基本的生化 理解与识别有关的几种复杂现象 通过 RNA 聚合酶启动大肠杆菌。 一系列研究将 表征“封闭配合物”，一种重要的反应中间体 启动过程。 体外进行的实验也将 表征突变西格玛亚基的特性，显示 改变启动子在体内的识别。 DNA超螺旋的影响 将使用新开发的测定法来探索启动子识别 拓扑异构体选择性。 这种新颖的方法将在一项研究中得到扩展 cap*cAMP 对乳糖和半乳糖操纵子的正向调节 发起人。 半乳糖对启动子选择性的调节 gal 启动子上的阻遏蛋白也将被表征。 结构性 RNA-RNA 配对的决定因素也将在以下示例中确定 反义RNA基因调控。 在这种情况下，监管发生 然而，主要是在翻译启动步骤中， 出现的RNA-RNA配对将适用于基因的许多其他步骤 表达及其调控。 我们提出的问题的答案 将有助于基因控制的生化描述 表达。