Genetic Analysis of Legionella Phagosome Trafficking

军团菌吞噬体贩运的遗传分析

基本信息

批准号：
9982749
负责人：
Craig R. Roy
金额：
$ 54.42万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-01 至 2022-07-31
项目状态：
已结题

项目摘要

Legionella pneumophila is the causative agent of a severe pneumonia called Legionnaires’ disease. The ability of Legionella to replicate inside of phagocytic cells is central to host pathogenesis and requires a specialized secretion system called Dot/Icm. The focus of this project has been to determine how the Dot/Icm system enables Legionella to create an intracellular vacuole that supports replication. Towards this end, we have demonstrated that this process involves the subversion of host vesicles derived from the endoplasmic reticulum, which are used by Legionella to remodel the plasma membrane-derived organelle it occupies initially into a vacuole that resembles the endoplasmic reticulum. Proteins delivered into host cells by the Dot/Icm system promote this membrane transport pathway. Over the past funding period we have identified multiple bacterial proteins that target the host membrane transport regulator Rab1. To understand how these proteins control membrane transport and promote biogenesis of a vacuole that permits Legionella intracellular growth, we will investigate the function of these proteins during infection of host cells by Legionella. Specifically, we will determine how the biochemical activities of these proteins are regulated spatially and temporally during infection to coordinate the cycling of Rab1 on vacuoles containing Legionella, determine how Rab1 activation on the vacuole containing Legionella can promote the recruitment and fusion of endoplasmic reticulum-derived vesicles, and determine the role host proteins that regulate phosphatidylinositol 4-phosphate play in vacuole maturation.

肺炎军团是一种称为军团疾病的严重肺炎的病因。军团菌在吞噬细胞内复制的能力对于宿主发病是至关重要的，需要一个称为DOT/ICM的专门分泌系统。该项目的重点是确定点/ICM系统如何使Legionella创建支持复制的细胞内真空吸尘器。为此，我们已经证明了这一过程涉及源自内质网的宿主蔬菜，该植物被Legionella用于重塑质膜衍生的细胞器，其最初占据的真空吸尘器将其重新固定在内质网中。 DOT/ICM系统输送到宿主细胞中的蛋白质促进了该膜转运途径。在过去的资金期间，我们已经确定了靶向宿主膜转运剂RAB1的多种细菌蛋白。为了了解这些蛋白质如何控制膜转运并促进允许军团内生长的真空吸尘器的生物发生，我们将研究这些蛋白质在通过军团菌感染宿主细胞期间这些蛋白质的功能。具体而言，我们将确定如何在感染过程中频繁和临时调节这些蛋白质的生化活性，以协调Rab1在含有军团菌的真空上的Rab1的循环，确定含有吸尘器的Rab1激活含有军团菌的Rab1激活如何促进募集和融合的肾脏肿瘤，以确定端质播种的植物和构成型的植物素质的素质范围4在真空成熟中。