The role of secreted effector proteins in Chlamydia trachomatis invasion

分泌效应蛋白在沙眼衣原体侵袭中的作用

• 批准号: 10468841
• 负责人: Mary Weber
• 金额: $ 49.01万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-22 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10468841
• 关键词: ANGPTL2 gene; Actins; Address; Antibiotics; Bacteria; Bacterial Infections; Binding; Blindness; Cells; Cervical; Chlamydia; Chlamydia trachomatis; Complex; Cytoskeletal Modeling; Cytoskeleton; Data; Defect; Development; Disease Progression; EMS1 gene; Ensure; Filopodia; Genetic; Glean; Goals; Guanosine Triphosphate Phosphohydrolases; Human; Impairment; Incidence; Infection; Injections; Integration Host Factors; Invaded; Knowledge; Laboratories; Left; Measures; Mediating; Membrane; Modeling; Molecular; Nature; Pathogenesis; Pathway interactions; Physiological; Prevalence; Process; Proliferating; Proteins; Recurrence; Role; Scaffolding Protein; Sexual Transmission; Signal Pathway; Signal Transduction; Site; Type III Secretion System Pathway; knock-down; mutant; novel; novel therapeutic intervention; pathogen; polymerization; recruit; tool; uptake

Project Summary Chlamydia trachomatis (C.t.) is the leading cause of non-congenital blindness and the most prevalent sexually transmitted bacterial infection in the world, which if left untreated can result in severe consequences. All chlamydiae are obligate intracellular bacteria and thus gaining entry into a host cell is essential for the pathogen to complete its replicative cycle and proliferate. Despite the critical nature of the invasion process, the molecular mechanisms and details regarding how C.t. forces its way into non-phagocytic cells remains a large knowledge gap. A major premise of the current model suggests that invasion is facilitated by delivery of prepackaged conventional type III secretion system (cT3SS) effector proteins into the host cell prior to pathogen entry. We hypothesize that a subset of these cT3SS effectors coordinate active subversion of the host cytoskeleton through direct manipulation of key regulators of actin dynamics. New data from our laboratory indicates that the cT3SS effector protein TmeA binds to the nucleation promoting factor N-WASP, both of which we show are essential for invasion. In Aim 1, we will mechanistically determine how TmeA regulates N-WASP and determine whether this interaction promotes key membrane features that likely aid in bacterial entry such as; membrane ruffling, pedestal formation, and filopodial dynamics. Given the essential nature of invasion to bacterial proliferation and survival, C.t. likely employs multiple measures for invasion. In Aim 2, we will evaluate the complex interplay between TarP, TepP, and TmeA and reveal the ultimate molecular effects of their effector function and describe how the seemingly disparate pathways targeted by these effectors converge to assure chlamydial invasion. Furthermore, we will determine whether other cT3SS effectors, only expressed in the invasive EB form of chlamydia, are necessary for invasion of non-phagocytic cells. Detailed characterization of the bacterial and host proteins required to promote reorganization of the actin cytoskeleton during C.t. invasion will provide a holistic view of how intracellular pathogens, such as C.t., coordinate subversion of cytoskeletal regulators to invade host cells.

项目摘要 衣原体沙眼（C.T.）是非占否盲目的主要原因，也是最普遍的性行为 在世界上传播细菌感染，如果没有治疗，可能会导致严重的后果。全部 衣原体是务本细胞内细菌，因此进入宿主细胞对于病原体至关重要 完成其复制周期并扩散。尽管入侵过程的性质很关键，但分子 有关C.T.的机制和细节将其进入非孢子细胞的力仍然是一个广泛的知识 差距。当前模型的主要前提表明，通过预先包装的交付来促进入侵 在病原体进入之前，常规的III型分泌系统（CT3SS）效应蛋白进入宿主细胞。我们 假设这些CT3S效应子的子集通过 直接操纵肌动蛋白动力学的关键调节剂。我们实验室的新数据表明CT3SS 效应蛋白TMEA与成核促进因子N-WASP结合，我们表明这都是必不可少的 入侵。在AIM 1中，我们将机械学确定TMEA如何调节N-WASP并确定是否是否 这种相互作用促进了可能有助于细菌进入的关键膜特征。膜褶皱， 基座形成和丝状动力学。鉴于对细菌增殖的侵袭的基本特性和 生存，C.T。可能采取多种入侵措施。在AIM 2中，我们将评估复杂的相互作用 在TARP，TEPP和TMEA之间，并揭示其效应函数的最终分子效应并描述 这些效应器的看似不同的途径如何汇聚以确保衣原体入侵。 此外，我们将确定其他CT3SS效应子是否仅以侵入性EB形式表示 衣原体是入侵非吞噬细胞所必需的。细菌和宿主的详细表征 C.T.中促进肌动蛋白细胞骨架的重组所需的蛋白质需要入侵将提供整体 查看细胞内病原体（例如C.T.）如何坐在细胞骨架调节剂的坐标以侵入宿主 细胞。