Regulation of RecA Intein splicing in M. tuberculosis

描述（由申请人提供）：本项目的长期目标是了解M。结核病（Mtb）在感染期间调节其对宿主环境的反应，使得可以开发针对结核病（TB）疾病的改进的干预策略和生物标志物。内含肽是一种移动的蛋白质元件，可以插入到它们所处的蛋白质中。这些内含肽的自催化切除导致其宿主蛋白的功能激活，为快速翻译后基因调控提供了理想的机制。内含肽存在于三种Mtb蛋白（DnaB、RecA和SufB）中，所有这些蛋白在暴露于哺乳动物感染期间遇到的DNA损伤条件后的DNA复制和恢复过程中具有中心作用。内含肽已在生物化学水平上被广泛研究，并已被开发作为蛋白质工程的工具。然而，关于内含肽在Mtb中的生物学作用知之甚少，尽管最近的研究表明用FDA批准的抗癌药物顺铂预防内含肽剪接抑制Mtb生长。这一试点 该项目将测试内含肽剪接受宿主相关环境条件调节的假设，并产生一种灵敏的基于荧光的功能获得报告系统，适用于监测感染期间细菌内的Mtb内含肽剪接。这项研究计划的完成将提供关键的概念和技术基础，也将需要为未来的研究解决的可能性，内含肽提供一种快速的形式的翻译后调节结核病在宿主感染。这项工作是特别高的影响，因为潜在的内含肽剪接建立新的模式，基因调控结核分枝杆菌，可能控制结核分枝杆菌复制宿主内，以及表现出的作用，内含肽剪接作为一个可能的药物靶标。

DESCRIPTION (provided by applicant): The long term goal of this project is to understand the means by which M. tuberculosis (Mtb) regulates its response to the host environment during infection, so that improved intervention strategies and biomarkers can be developed against tuberculosis (TB) disease. Inteins are mobile protein elements that insertionally inactivate the proteins they inhabit. Autocatalytic excision of these inteins results in functional activation of their host proteins, providing an ideal mechanism for rapid post-translational gene regulation. Inteins are found in three Mtb proteins (DnaB, RecA and SufB), all of which have central roles in the process of DNA replication and recovery following exposure to the DNA damaging conditions encountered during mammalian infection. Inteins have been extensively studied at the biochemical level and have been exploited as tools for protein engineering. However, little is known about the biological roles of inteins in Mtb despite recent studies showing that prevention of intein splicing with the FDA approved anti-cancer drug cisplatin inhibits Mtb growth. This pilot project will test the hypothesis that intein splicing is modulated by host-associated environmental conditions and generate a sensitive fluorescence-based gain-of-function reporter system suitable for monitoring Mtb intein splicing within bacteria during infection. Completion of this research plan will provide critical conceptual and technical foundations that will also be needed for future studies addressing the possibility that inteins provide a rapid form of post-translational regulation in Mtb during host infection. This work is of particularly high impact because of the potential for intein splicing to establish new paradigms for gene regulation in Mtb that may control Mtb replication within the host, as well as the demonstrated role of intein splicing as a possible drug target.