Establishment of an aqueous environment as a novel mechanism of bacterial pathogenesis

建立水环境作为细菌发病机制的新机制

• 批准号: 10267699
• 负责人: SHENG YANG HE
• 金额: $ 39.51万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-21 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10267699
• 关键词: 26S proteasome; ADP-Ribosylation Factors; Affect; Air; Animals; Arabidopsis; Bacteria; Bacterial Infections; Biochemical Genetics; Biochemistry; Biological; Cell membrane; Cells; Cellular biology; Communicable Diseases; Development; Dimensions; Disease; Early Endosome; Environment; Epidermis; Family; Gases; Genetic; Goals; Golgi Apparatus; Guanine Nucleotide Exchange Factors; Homeostasis; Human; Immunity; Infection; Infection Control; Innate Immune Response; Kidney; Knowledge; Laboratories; Lead; Link; Malignant Neoplasms; Mammals; Measures; Mediating; Methods; Michigan; Microbe; Modeling; Molecular Genetics; Mouse-ear Cress; Mucous body substance; Natural Immunity; Nature; Organ; Pathogenesis; Pathway interactions; Phosphorylation; Plant Leaves; Plants; Principal Investigator; Proliferating; Proteins; Pseudomonas syringae; Regulation; Research; Respiratory System; Role; Skin; Testing; Tissues; Type III Secretion System Pathway; Universities; Vesicle; Virulence; Water; Yang; aqueous; calcium-dependent protein kinase; enteropathogenic Escherichia coli; extracellular; host microbiome; host-microbe interactions; in vivo; innovation; insight; microbial; microbiome; novel; pathogen; pathogenic bacteria; prevent; ubiquitin-protein ligase; water channel

Establishment of an aqueous environment as a novel mechanism of bacterial pathogenesis PI: HE, Sheng Yang; Michigan State University Project summary Many bacterial pathogens of plants and mammals, including humans, use the highly conserved type III secretion system (T3SS) to inject “effector proteins” into the host cell as an important paradigm of pathogenesis. The long-term goal of this project is to characterize a newly discovered T3SS-mediated virulence strategy by which bacterial pathogens create an aqueous extracellular environment in host tissues. In nature, many host-pathogen and host-microbiome interactions occur in air-exposed/connected host organs/tissues (e.g., epidermis/skin and gas-exchange organs including respiratory systems and plant leaves) in which water availability is limited and/or variable. Because microbes generally require a moist/aqueous/mucous environment to survive and proliferate, it is not well understood whether microbes actively establish an infection-conducive aqueous environment in host organs. In humans, malfunction of aquaporins has been associated with infectious diseases, kidney malfunction and even cancer development and there is an emerging link between aquaporin- mediated water transport and pathogenesis of enteropathogenic Escherichia coli. However, cause-effect relationships often remain unclear. In the past 25 years, the Principal Investigator’s lab has used the model Arabidopsis thaliana – Pseudomonas syringae interaction to discover and characterize T3SS-mediated bacterial infection mechanisms. By taking advantage of the genetic tractability of Arabidopsis and a well-characterized T3SS effector repertoire in P. syringae, the PI’s lab recently discovered a critical role of an aqueous environment in bacterial pathogenesis. In this application, three specific aims are proposed to test the central hypothesis that, by altering (i) ARF-GEFMIN7-dependent vesicular traffic and (ii) phosphorylation of aquaporins involved in regulating water transport across host plasma membrane, P. syringae disrupts water homeostasis across the host plasma membrane, resulting in an aqueous extracellular environment as an important mechanism of pathogenesis. Aim 1 will determine the role of ARF-GEFMIN7-associated host proteins in regulating vesicular traffic of aquaporins and extracellular water. Aim 2 will investigate how P. syringae T3SS effector proteins target ARF-GEFMIN7- associated vesicle traffic and aquaporins to induce an aqueous extracellular environment. Aim 3 will elucidate how activation of host immunity prevents the virulence actions of P. syringae T3SS effectors as a novel dimension of the host innate immune response. Contemporary methods in molecular genetics, cell biology, biochemistry and microbial pathogenesis will be used in this study. Successful completion of this research will significantly advance our understanding of a newly discovered bacterial virulence mechanism and its interplay with host innate immunity. As many host-microbe interactions occurs in air-connected host organs/tissues, in which water availability is restricted, it is hoped that this original research will stimulate studies to broadly examine water regulation in other host-pathogen interactions, and, in the long- term, facilitate the development of innovative and broadly applicable measures for controlling infectious diseases in diverse eukaryotic hosts, including plants, animals and humans.

建立水环境作为细菌发病机制的新机制 PI：何盛阳；密歇根州立大学 项目概要 植物和哺乳动物（包括人类）的许多细菌病原体都使用高度保守的 III 型分泌系统 （T3SS）将“效应蛋白”注入宿主细胞作为发病机制的重要范例。本次活动的长远目标 该项目的目的是描述一种新发现的 T3SS 介导的毒力策略，细菌病原体通过该策略产生 宿主组织中的水性细胞外环境。在自然界中，许多宿主-病原体和宿主-微生物组相互作用发生 在暴露于空气/连接的宿主器官/组织中（例如表皮/皮肤和气体交换器官，包括呼吸系统） 和植物叶子），其中可用水量有限和/或可变。因为微生物一般需要 潮湿/水/粘液环境中生存和增殖，目前尚不清楚微生物是否主动建立 宿主器官内有利于感染的水环境。在人类中，水通道蛋白的功能障碍与 传染病、肾功能障碍甚至癌症的发展，水通道蛋白与 介导的肠道病原性大肠杆菌的水运输和发病机制。然而，因果关系往往 仍不清楚。在过去的25年里，首席研究员的实验室使用了模型拟南芥-假单胞菌 丁香菌相互作用，以发现和表征 T3SS 介导的细菌感染机制。通过利用 PI 实验室最近研究了拟南芥的遗传易处理性和丁香假单胞菌中特征明确的 T3SS 效应子库 发现水环境在细菌发病机制中的关键作用。在此应用程序中，三个具体目标是 提议测试中心假设，即通过改变 (i) ARF-GEFMIN7 依赖性囊泡运输和 (ii) 磷酸化 水通道蛋白参与调节跨宿主质膜的水运输，丁香假单胞菌破坏水稳态 穿过宿主质膜，产生水性细胞外环境作为重要机制 发病。目标 1 将确定 ARF-GEFMIN7 相关宿主蛋白在调节囊泡运输中的作用 水通道蛋白和细胞外水。目标 2 将研究丁香假单胞菌 T3SS 效应蛋白如何靶向 ARF-GEFMIN7- 相关的囊泡交通和水通道蛋白诱导水性细胞外环境。目标 3 将阐明如何 宿主免疫的激活可防止丁香假单胞菌 T3SS 效应子作为宿主的新维度的毒力作用 先天免疫反应。分子遗传学、细胞生物学、生物化学和微生物的现代方法 本研究将使用发病机制。成功完成这项研究将极大地增进我们的理解 新发现的细菌毒力机制及其与宿主先天免疫的相互作用。与许多宿主微生物一样 相互作用发生在与空气相连的宿主器官/组织中，其中水的可用性受到限制，希望这种原始的 研究将刺激广泛研究其他宿主与病原体相互作用中的水调节，并且从长远来看 长远来看，促进制定创新且广泛适用的措施来控制不同地区的传染病 真核宿主，包括植物、动物和人类。