结核分枝杆菌中转录因子介导的耐药调控机制研究

Tuberculosis (TB) has been a menace to human health throughout the world. The drug resistance of Mycobacterium tuberculosis has become an extremely serious problem to any attempt to control TB. It is basically known that acquired resistance to the first-line antibiotics because of sequential accumulation of mutations in target genes has resulted in the emergence of drug resistant TB. However, the additional regulating mechanisms on the drug restance of M. tuberculosis are largely unclear and the involved transcription factor remains to be identified. In this proposal, we will firstly clone almost entire regulatory genes from the genome of M. tuberculosis into overexpression plasmids and screen potential regulators which can obviously affect the ability of the mycobacterial drug resistance. Then, using multiple methods, including EMSA, ChIP, transcriptomics, proteomics and gene knock-out assays, we will comprehensively characterize the interaction between the regulator and the target promoter DNA, and discover new signaling pathways in the pathogen. Finally, we will explore on the relationships betwen the regulator-involved signaling pathways and mycobacterial drug-resistance. Therefore, this study would significantly improve our understanding on the transcription regulatory mechanisms of the bacterial drug-resistance in M. tuberculosis. This also will definitely help explore new drug target and develop ideal stretgy for finally controling TB in the future.

结核病全球蔓延，细菌耐药问题十分严重。然而，尽管目前已经清楚药物靶标基因突变是导致临床菌株耐药的主要原因，但是有关结核分枝杆菌耐药性形成的其它调控机制还知之甚少，相关的调控因子也还未系统地鉴定。为此，本项目拟首先大规模克隆结核分枝杆菌的转录调控基因，构建基因超量表达文库，系统筛选对结核分枝杆菌药物抗性能力有显著影响的转录因子。在此基础上，进一步采用EMSA、ChIP、转录组学和蛋白质组学分析以及基因敲除等方法，综合鉴定这些转录因子蛋白与它们的靶启动子DNA之间的相互作用，发现和剖析相关信号通路，从而系统阐明结核分枝杆菌中转录因子介导的细菌耐药调控新机制。本项目的实施将能显著提升我们对基因转录调控导致结核分枝杆菌耐药性形成的分子机制的认识，有助于推动新药靶标的发掘，为结核病的防控提供新思路。

结核病全球蔓延，细菌耐药问题十分严重。但是有关结核分枝杆菌耐药性形成的调控机制还知之甚少，相关的调控因子也还未系统地鉴定。本项目通过大规模克隆结核分枝杆菌的转录调控基因，系统筛选了对结核分枝杆菌药物抗性能力有显著影响的转录因子。发现了一个新的保守的拟核结合蛋白NapM具有弯曲和桥连DNA的功能, 能调控分枝杆菌对抗结核药物的抗性; 证明了由Rv0273c基因编码的TetR家族转录因子EtbR是一种新的乙胺丁醇结合蛋白，它在两种一线抗结核药物异烟肼和乙胺丁醇的协同作用中发挥重要作用; 发现和命名了一个抗结核药物异烟肼作用的新靶标调控因子蛋白InbR，并阐明了调控机制; 阐明了c-di-GMP分子调控结核分枝杆菌生长和在宿主体内存活的新机制。这些工作显著提升了我们对基因转录调控导致结核分枝杆菌耐药性形成的分子机制的认识，有助于推动新药靶标的发掘，为结核病的防控提供新思路。