GENE CONTROL IN INFECTION AND LYSOGENY BY PHAGE LAMBDA

噬菌体 Lambda 对感染和溶原的基因控制

• 批准号: 7171498
• 负责人: JEFFREY W ROBERTS
• 金额: $ 63.13万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-02-01 至 2009-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7171498
• 关键词: Affect; Affinity; Affinity Chromatography; Bacteriophage lambda; Binding; Biological Assay; Characteristics; Chemicals; Complex; Condition; DNA Binding; DNA Sequence; DNA-Directed RNA Polymerase; Defect; Elements; Enzymes; Escherichia coli Proteins; Evolution; Family; Gene Expression; Genes; Genetic Transcription; HIV; Holoenzymes; In Vitro; Infection; Lysogeny; Mediating; Modeling; Modification; Molecular Machines; Mutation; Oligonucleotides; Process; Property; Proteins; RNA; Role; Sigma Factor; Signal Transduction; Site; Structure; Suppressor Mutations; Transcript; Transcription Initiation; Transcriptional Regulation; antitermination; base; genetic regulatory protein; in vivo; polypeptide; transcription termination; vif Genes; yeast two hybrid system

Gene expression in normal and pathological conditions is mediated by RNA polymerase enzymes, a family of complex, multisubunit molecular machines that is highly conserved in evolution. RNA polymerase function is controlled not only at the level of access to genes (transcription initiation), but also during enzyme progression as RNAP carries out its sequential readout of the gene message. An important example of such control occurs in HIV virus and is mediated by its major regulator, the TAT gene. The central models for understanding enzymatic mechanisms involved in transcriptional regulation are the antitermination proteins of the E. coli bacteriophage lambda, the products of its genes Q and N. This project studies the mechanism of action of the gene Q protein, which modifies RNA polymerase near its initiation site, but then becomes a subunit of the enzyme, allowing it to elongate more efficiently and to progress through transcription termination signals. We will discover important elements of both the Q polypeptide and the subunits of RNA polymerase that are required for their physical and functional interaction, particularly the sigma initiation factor which mediates the initial engagement of Q protein with RNA polymerase, and we will study the altered enzymatic properties of Q-modified RNA polymerase. We will investigate the mechanism of transcription termination and the manner in which regulatory proteins interfere with this process.

正常和病理条件下的基因表达是由RNA聚合酶介导的 酶，一个复杂的多亚基分子机器家族，是高度的 在进化中保守。 RNA聚合酶功能不仅在控制水平上受到控制 获取基因（转录启动），但在酶进程中也作为RNAP 进行基因消息的顺序读数。这样的重要例子 控制发生在HIV病毒中，并由其主要调节剂TAT基因介导。这 理解转录涉及的酶机制的中心模型 调节是大肠杆菌噬菌体lambda的抗授权蛋白， 其基因Q和N的产物。该项目研究基因的作用机理 Q蛋白质，它在其启动位点附近修饰RNA聚合酶，但随后变成一个 酶的亚基，使其更有效地伸长并通过 转录终止信号。我们将发现两个Q的重要元素 多肽和RNA聚合酶的亚基是其物理和 功能相互作用，尤其是介导初始的Sigma启动因子 Q蛋白与RNA聚合酶的参与，我们将研究改变的酶促 Q修饰的RNA聚合酶的性能。我们将研究的机制 转录终止和调节蛋白干扰的方式 这个过程。