Regulation of gene expression in Borrelia burgdorferi

伯氏疏螺旋体基因表达的调控

• 批准号: 8967130
• 负责人: D. SCOTT SAMUELS
• 金额: $ 35.38万
• 依托单位: UNIVERSITY OF MONTANA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-05 至 2018-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8967130
• 关键词: 6S RNA; Affect; Arthropods; Bacteria; Bacteria sigma factor KatF protein; Binding; Biochemical; Biochemical Genetics; Biological Assay; Borrelia burgdorferi; Case Study; DNA-Directed RNA Polymerase; Data; Diagnostic; Endoribonucleases; Enzymes; Funding; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Transcription; Guanosine Tetraphosphate; Health; Holoenzymes; Homologous Gene; Housekeeping; Human; Incidence; Infection; Ixodes; Knowledge; Laboratories; Lead; Lyme Disease; Mammals; Mediating; Messenger RNA; Microbiology; Mission; Molecular; Molecular Chaperones; Mus; Nature; Nutrient; Order Spirochaetales; Pathogenesis; Pathway interactions; Phase; Prevention; Process; Production; Proteins; Proteomics; RNA; Regulation; Regulon; Research; Ribonucleases; Role; Sigma Factor; Signal Transduction; Signaling Molecule; Small RNA; Stress; Testing; Ticks; Transcript; Translations; United States; base; disease transmission; enzootic; feeding; genetic regulatory protein; human disease; improved; in vivo; mouse model; novel; programs; promoter; response; transcriptomics; transmission process; treatment strategy; vector

DESCRIPTION (provided by applicant): Lyme disease is caused by infection with the spirochete Borrelia burgdorferi. B. burgdorferi is maintained in nature through an enzootic cycle comprising a tick vector and vertebrate host. Transmission from the tick to the mammal and establishment of the mammalian infection require sensing external signals and responding by regulating programs of gene expression. This change in gene expression is predominantly mediated by the alternative sigma factor RpoS. The central hypothesis of this application is that RpoS is the principal transcriptional regulator controlling transmission to and infection of the mammalian host, and thus serves as the target of several regulatory mechanisms. We propose to dissect the mechanisms controlling rpoS expression and RpoS activity on downstream targets. Specifically, we hypothesize that a novel rpoS transcript has a distinct role in transmission and is processed by a recently identified endoribonuclease; the signaling molecule guanosine tetraphosphate, and associated regulatory proteins, globally affect RpoS-mediated transcription and translation throughout the enzootic cycle; and a small regulatory RNA affects sigma factor selectivity and activity. The long-term objective of this proposal is to understand th role and regulation of RpoS in tick-to-mammal transmission and disease pathogenesis, which will lead to improved diagnostic, prevention, and treatment strategies because RpoS is required for B. burgdorferi to cause Lyme disease; this is relevant to the mission of the agency to "seek fundamental knowledge" for the sake of alleviating human disease. The following specific aims are proposed toward achieving this objective: 1) determine the role of, and processing mechanism for, the novel rpoS transcript; 2) elucidate the targets and function of guanosine tetraphosphate during the enzootic cycle; and 3) characterize a small RNA that regulates sigma factor selectivity. Genetic, biochemical, transcriptomic, and proteomic approaches will be utilized to test these hypotheses. Specifically, genes encoding regulatory factors (or the production of regulatory factors) will be disrupted and/or fused to an inducible promoter to assay in vivo function in a tick-mouse model.

描述（由申请人提供）：莱姆病是由螺旋体Borrelia burgdorferi感染引起的。 B. Burgdorferi在本质上通过包含tick矢量和脊椎动物宿主的enzootic循环保持。从哺乳动物的壁虱传播和哺乳动物感染的建立需要感知外部信号，并通过调节基因表达程序来做出反应。基因表达的这种变化主要由替代的Sigma因子RPO介导。 该应用的中心假设是RPO是控制哺乳动物宿主传播和感染的主要转录调节剂，因此是几种调节机制的目标。我们建议剖析控制下游目标上RPOS表达和RPOS活性的机制。具体而言，我们假设一种新型的RPOS转录本在传播中具有独特的作用，并且通过最近确定的内核酸酶处理。在整个enzootic循环中，信号分子四磷酸四磷酸和相关的调节蛋白都会影响RPOS介导的转录和翻译。一个小的调节RNA会影响Sigma因子的选择性和活性。该提议的长期目标是了解RPO在乳房传播和疾病发病机理中的角色和调节，这将导致改善诊断，预防和治疗策略，因为RPO是B. burgdorferi需要引起莱姆病的rpos；这与该机构为了减轻人类疾病而“寻求基本知识”的使命相关。 提出了以下特定目的来实现这一目标：1）确定新型RPOS转录本的作用和处理机制； 2）阐明在enzootic循环中鸟苷四磷酸盐的靶和功能； 3）表征一个调节Sigma因子选择性的小RNA。遗传，生化，转录组和蛋白质组学方法将用于检验这些假设。具体而言，编码调节因子（或监管因素的产生）的基因将被破坏和/或融合到诱导型启动子中，以在tick鼠模型中分析体内功能。