The cellular mechanisms underpinning the host restriction of Salmonella Typhi

伤寒沙门氏菌宿主限制的细胞机制

基本信息

批准号：
MR/M011771/2
负责人：
Daniel Humphreys
金额：
$ 45.13万
依托单位：
University of Sheffield
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2016
资助国家：
英国
起止时间：
2016 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=MR%2FM011771%2F2
关键词：
cellular mechanisms underpinning host restriction

项目摘要

The bacterial pathogen Salmonella Typhi causes a severe systemic disease in humans called typhoid fever, which is of major global importance and results in over 27 million cases of disease and 200,000 deaths each year. S.Typhi is a host-adapted pathogen that is exclusively restricted to humans but the disease mechanisms governing this host specificity are unknown.S.Typhi initiates typhoid fever by injecting virulence proteins into human host cells to direct uptake and replication within an intracellular membrane-bound compartment called the Salmonella-containing vacuole (SCV). S.Typhi is incapable of establishing infection in mouse cells where the mammalian Rab32 GTPase localises to the SCV and directs the pathogen for degradation. When Rab32 is eliminated from cells using genetic engineering S.Typhi survives within a mouse. This shows that Rab32 is critical for the pathogen's strict host-specificity. The Rab GTPase family (~60 members) control cellular communication pathways by recruiting specialised 'effector' proteins to membrane-bound compartments. How mouse Rab32 destroys S.Typhi, and through which effectors, is unknown. Strikingly, human Rab32 localises to SCVs in infected human cells where the pathogen survives and establishes infection. This demonstrates a critical difference in the mouse and human Rab32 pathways. How S.Typhi survives the action of human Rab32 and its cognate effectors is not understood.Fundamental to Rab function is the membrane to which they are anchored but studying this presents formidable challenges. I propose to build a new experimental reconstitution approach that tackles this very important problem by focusing on the key relationship between Rabs and their membrane. I will engineer membrane-bound particles displaying host-specific Rab32 that will mimic SCVs in mouse and human cell-free extracts. In this way, I will capture and identify the mystery Rab32 effectors, and understand how they operate fundamentally in the physiological membrane environment. SCV proteomics and infection-based screens will form complementary approaches for identifying the pivotal Rab32 effectors. The role and regulation of the Rab32-effectors and their interaction with intracellular S.Typhi will be determined during infection of mouse and human cells. Resolving the cellular mechanisms of S.Typhi's host restriction will reveal pivotal cell biology underlying typhoid, and has the potential to speed the development of our anti-infectives arsenal and broaden the scope for therapeutic intervention. Furthermore, the powerful reconstitution system would be applicable to any Rab GTPase combination making it an effective tool for multiple research avenues in the future addressing human diseases.

细菌病原体斑疹伤寒鼠伤寒会引起严重的全身性疾病，称为伤寒，这是全球重要性的主要重要性，每年导致超过2700万例疾病和200,000例死亡。 S. typhi是一种宿主适应的病原体，仅限于人类，但管理该宿主特异性的疾病机制是未知的。绑定的隔室称为含沙门氏菌的液泡（SCV）。 S. typhi无法在小鼠细胞中建立感染，其中哺乳动物RAB32 GTPase局部局部到SCV并指导病原体降解。当使用基因工程从细胞中消除RAB32时，S.TYPHI在小鼠中存活。这表明RAB32对于病原体的严格宿主特异性至关重要。 RAB GTPase家族（约60个成员）通过将专门的“效应子”蛋白募集到膜结合的隔室来控制细胞通信途径。小鼠rab32如何破坏s.typhi以及效应子是未知的。令人惊讶的是，人类Rab32在感染的人类细胞中生存并建立感染的人类SCV的位置。这证明了小鼠和人类RAB32途径的批判差异。 S.Typhi如何在人类Rab32及其认知效应子的作用中生存下来。对Rab功能的资料是锚定的膜，但研究了这一挑战。我建议建立一种新的实验性重组方法，该方法通过关注Rabs及其膜之间的关键关系来解决这个非常重要的问题。我将设计出膜结合的颗粒，这些颗粒显示出宿主特异性RAB32，该颗粒将模仿小鼠和无细胞提取物中的SCV。通过这种方式，我将捕获并确定神秘的RAB32效应子，并了解它们在生理膜环境中的根本操作。 SCV蛋白质组学和基于感染的筛选将形成识别关键RAB32效应子的互补方法。在小鼠和人类细胞感染期间，将确定RAB32效应的作用和调节及其与细胞内typhi的相互作用。解决S.Typhi宿主限制的细胞机制将显示伤寒潜在的关键细胞生物学，并有可能加快我们抗感染药物的发展，并扩大治疗干预的范围。此外，强大的重建系统将适用于任何RAB GTPase组合，这使其成为未来针对人类疾病的多个研究途径的有效工具。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

MYO6 is targeted by Salmonella virulence effectors to trigger PI3-kinase signaling and pathogen invasion into host cells

DOI：
10.1073/pnas.1616418114
发表时间：
2017-04-11
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
影响因子：
11.1
作者：
Brooks, Andrew B. E.;Humphreys, Daniel;Koronakis, Vassilis
通讯作者：
Koronakis, Vassilis

Arf GTPase interplay with Rho GTPases in regulation of the actin cytoskeleton.