M.tuberculosis Genes Regulating Persistent Infection

结核分枝杆菌调节持续感染的基因

• 批准号: 6632810
• 负责人: THOMAS C. ZAHRT
• 金额: $ 30万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-15 至 2006-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6632810
• 关键词: Animalia; Mycobacterium tuberculosis; bacteria infection mechanism; biological signal transduction; cellular immunity; cytokine; gene expression; genetic manipulation; genetic mapping; genetic promoter element; genetic regulation; human tissue; macrophage; molecular pathology; virulence

DESCRIPTION (provided by applicant) Tuberculosis is the leading cause of death in the world from a single infectious agent, and is responsible for more than 3 million deaths annually. The high mortality rate in individuals infected with Mycobacterium tuberculosis is due in part to its ability to parasitize macrophages and establish long-term, persistent infection in the host despite cell-mediated immunity. Although the current anti-tubercular drug arsenal is effective in treating individuals suffering from active disease, these drugs are ineffective in treating the 2 billion people that currently suffer from latent tuberculosis, or that are infected with multi-drug resistant strains of M. tuberculosis. One group of transcriptional regulatory determinants that may play a critical role in processes associated with M. tuberculosis latency is the two-component signal transduction systems. These systems mediate adaptation processes and have been shown to contribute to virulence and disease elicitation in other organisms. The goals of this study are to characterize further a two-component system of M. tuberculosis (MprA-MprB) that is required for the establishment and maintenance of persistent infection. In this proposal, we plan to: (i) Identify and characterize the genes regulated by the MprA transcription factor. The genes regulated by MprA will be identified from the M. tuberculosis chromosome using biochemical enrichment and genetic selection techniques, and will be characterized by gene inactivation, promoter expression analysis, and evaluation in model systems for infection. (ii) Analyze the in vivo expression profile of the MprA response regulator, and the genes regulated by MprA. This will be accomplished by expression analysis of these genes using GFP reporter technology, primer extension analysis, molecular beacon technology, and DNA microarray based analysis under physiologically relevant conditions. (iii) Delineate the effects of MprA de-regulation on host-pathogen interactions. This will be accomplished by examining effects of MprA loss or overexpression on M. tuberculosis virulence. Virulence studies will include bacterial survival and cytokine expression analysis as assayed in in vitro tissue culture systems and animal model systems of infection. These studies will also address the effects of MprA de-regulation on Mycobacterium bovis BCG attenuation. The proposal outlined here is expected to improve our understanding of genes required by M. tuberculosis for pathogenesis, and help better define the conditions encountered and responses utilized by M. tuberculosis during the latent stage of infection. We hope that the analysis of two-component systems will aid in the identification of genetic determinants for which novel anti-tubercular drugs can be developed.

描述（由申请人提供） 结核病是世界上死亡的主要原因 感染力，每年造成超过300万人死亡。 感染分枝杆菌的个体的高死亡率 结核病的部分原因是它能够寄生巨噬细胞和 尽管细胞介导 免疫。 尽管当前的抗结核药武器库有效 治疗患有活性疾病的人，这些药物是 无效治疗目前患有潜在的20亿人 结核病，或感染了M的多药抗性菌株。 结核。 一组转录调节决定因素 在与结核分枝杆菌潜伏期相关的过程中起关键作用是 两个组件信号转导系统。 这些系统介导 适应过程，已被证明有助于毒力和 其他生物体的疾病诱导。 这项研究的目标是 进一步表征结核分枝杆菌的两组分系统（MPRA-MPRB） 这是建立和维护持久性所必需的 感染。 在此提案中，我们计划：（i）确定并表征 由MPRA转录因子调节的基因。 由MPRA调节的基因 将使用生化从结核分枝杆菌染色体鉴定 富集和遗传选择技术，将以基因为特征 模型系统中的灭活，启动子表达分析和评估 感染。 （ii）分析MPRA的体内表达谱 响应调节剂和由MPRA调节的基因。 这将是 通过使用GFP报告基因对这些基因的表达分析完成 技术，底漆扩展分析，分子信标技术和DNA 在生理上相关条件下基于微阵列的分析。 （iii） 描述MPRA消除调节对宿主病原体相互作用的影响。 这将通过检查MPRA损失或过表达的影响来实现 关于结核病毒力。 毒力研究将包括细菌 在体外组织中测定的生存和细胞因子表达分析 培养系统和动物模型感染系统。 这些研究会 还解决了MPRA消除调节对牛分枝杆菌BCG的影响 衰减。 预计此处概述的提案将改善我们的 了解结核分枝杆菌需要发病机理所需的基因，并有助于 更好地定义遇到的条件和M。 在感染潜在阶段的结核病。 我们希望分析 两个组分系统的系统将有助于识别遗传 可以开发出新的抗结核药物的决定因素。