Regulation and composition of ER-inclusion contacts at key stages of the Chlamydia developmental cycle

摘要 沙眼衣原体是全世界细菌性传播感染的主要原因。 目前还没有疫苗。感染通常是无症状的，不进行治疗，导致组织瘢痕形成和 对女性生殖健康的长期影响。沙眼衣原体是一种专有的细胞内细菌路径- 在称为包涵体的膜结合室内经历两个阶段的发育周期的Ogen 西翁。沙眼衣原体必须与胞质寄主因子和组织因子相互作用，才能在这种有限的环境中茁壮成长。 通过插入衣原体特异性包涵膜蛋白(INC蛋白)介导的一种过程 进入包涵体膜。一种这样的相互作用是包括-的离散部分之间的亲密接触 Sion膜和内质网(ER)。这些结构被称为内质网包涵膜 联系地点(MCS)。我们对内质网包涵体MCS的初步表征表明，Inc蛋白和 具有功能、系留和监管能力的宿主因素。其中一些组件的耗尽是 不利于细菌生长，强调了内质网包涵体MCS在建立 可复制的利基市场。内质网包含的MCs在整个发育周期中都可以观察到；然而，它仍然 不清楚功能性、结构性和规则性组件是否以及如何在临时组装和 接触的不均匀，以及特定成分的浓缩。在这里，我们将调查ER包含如何 MCS组装受到监管(目标1)，如果特定组件的关联根据阶段的不同而变化 发育周期(目标2)。总之，拟议的研究将阐明内质网内含物的组成成分 MCS允许沙眼衣原体复制生态位的建立，这将指导有效的 治疗学。

SUMMARY Chlamydia trachomatis is the leading cause of sexually transmitted infections of bacterial origin worldwide. Vaccines are not available. Infections are often asymptomatic and left untreated, resulting in tissue scarring and long-term consequences on female reproductive health. C. trachomatis is an obligate intracellular bacterial path- ogen that undergoes a bi-phasic development cycle within a membrane bound compartment termed the inclu- sion. To thrive in this confined environment, C. trachomatis must interact with cytosolic host factors and orga- nelles, a process mediated by the insertion of Chlamydia specific Inclusion membrane proteins (Inc proteins) into the inclusion membrane. One such interaction is the intimate contact between discrete sections of the inclu- sion membrane and the endoplasmic reticulum (ER). These structures are referred to as ER-Inclusion membrane contact sites (MCS). Our initial characterization of ER-Inclusion MCS indicates an enrichment in Inc proteins and host factors with functional, tethering and regulatory capacities. Depletion of some of these components is detrimental to bacterial growth, underscoring the important role of ER-Inclusion MCS in establishing the replicative niche. ER-Inclusion MCS are observed throughout the developmental cycle; however, it remains unclear if and how functional, structural and regularoty components cooperate in the temporal assembly and dissambly of the contact, and enrichment of specific components. Here we will investigate how ER-Inclusion MCS assembly is regulated (Aim 1) and if association of specific components varies depending on the stage of the developmental cycle (Aim 2). Altogether, the proposed studies will elucidate how components of ER-Inclusion MCS allows for the establishment of the C. trachomatis replicative niche, which will guide the design of effective therapeutics.