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） 结核病是世界上导致死亡的主要原因， 它是一种传染性病原体，每年造成300多万人死亡。 结核分枝杆菌感染者的高死亡率 结核病的部分原因是它能够寄生于巨噬细胞， 在宿主中建立长期、持续的感染， 免疫力 虽然目前的抗结核药物库是有效的， 治疗患有活动性疾病的个体，这些药物 治疗目前20亿患有潜伏性 结核病，或感染了多重耐药的M. 结核 一组转录调控决定簇， 在与M.结核潜伏期是 双组分信号转导系统。 这些系统介导 适应过程，并已被证明有助于毒力和 在其他生物体中引发疾病。 本研究的目的是 进一步表征M的两组分系统。结核病（MprA-MprB） 建立和维护持久的 感染 在本提案中，我们计划：（i）识别和描述 受MprA转录因子调控的基因。 MprA调控的基因 将从M.结核病染色体生化法 富集和遗传选择技术，并将其特征在于基因 模型系统中的失活、启动子表达分析和评估 感染 (ii)分析MprA的体内表达谱 反应调节因子，以及由MprA调节的基因。 这将是 通过使用GFP报告基因对这些基因进行表达分析来完成 技术、引物延伸分析、分子信标技术和DNA 在生理相关条件下进行基于微阵列的分析。 （三） 描述MprA失调对宿主-病原体相互作用的影响。 这将通过检查MprA缺失或过表达的影响来实现。 滨海蒙特勒伊的结核病毒力 毒力研究将包括细菌 如在体外组织中测定的存活和细胞因子表达分析 培养系统和感染的动物模型系统。 这些研究将 还阐述了MprA去调节对牛分枝杆菌BCG的影响 衰减 这里概述的建议预计将改善我们的 了解M.结核病的发病机制，并帮助 更好地定义M遇到的条件和使用的响应。 结核病在感染的潜伏期。 我们希望分析 双组分系统将有助于识别遗传 可以开发新型抗结核药物的决定因素。