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: 10293988
• 负责人: SHENG YANG HE
• 金额: $ 39.43万
• 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/10293988
• 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.

水环境作为细菌致病新机制的建立 派：何胜阳；密歇根州立大学 项目总结 许多植物和哺乳动物的细菌病原体，包括人类，都使用高度保守的III型分泌系统。 (T3SS)将“效应蛋白”注入宿主细胞作为重要的致病范式。这样做的长期目标是 项目是表征一种新发现的T3SS介导的毒力策略，通过这种策略，细菌病原体可以创建 宿主组织中的水胞外环境。在自然界中，存在许多寄主-病原体和寄主-微生物组相互作用 暴露在空气中/连接的宿主器官/组织(例如，表皮/皮肤和包括呼吸系统在内的气体交换器官 和植物叶片)，其中水的可用性是有限的和/或可变的。因为微生物通常需要一种 潮湿/水/粘液环境下的生存和繁殖，目前还不清楚微生物是否积极地建立 宿主器官中有利于感染的水环境。在人类中，水通道蛋白的故障与 感染性疾病，肾功能障碍，甚至癌症的发展，水通道蛋白- 肠道致病性大肠埃希菌介导的水转运与致病机制。然而，因果关系往往 目前仍不清楚。在过去的25年里，首席研究员的实验室使用了拟南芥-假单胞菌模型 丁香科相互作用以发现和表征T3SS介导的细菌感染机制。通过利用 拟南芥的遗传可控性和紫丁香科植物T3SS效应谱的研究 发现了水环境在细菌致病中的关键作用。在此应用程序中，有三个具体目标 提出通过改变(I)依赖ARF-GEFMIN7的囊泡运输和(Ii)磷酸化来检验中心假设 在调节水跨宿主质膜运输的水通道蛋白中，丁香假单胞菌破坏了水的动态平衡 穿过宿主质膜，导致水胞外环境作为一种重要机制 发病机制。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。AIM 2将研究紫丁香菌T3SS效应蛋白如何靶向ARF-GEFMIN7- 相关的囊泡交通和水通道蛋白，以诱导水的细胞外环境。目标3将阐明如何 激活宿主免疫可抑制丁香疫霉T3SS效应子的毒力作用 先天免疫反应。分子遗传学、细胞生物学、生物化学和微生物学的当代方法 本研究将探讨其发病机制。这项研究的成功完成将极大地促进我们对 一种新发现的细菌毒力机制及其与宿主天然免疫的相互作用。同样多的寄主微生物 相互作用发生在空气连接的宿主器官/组织中，其中水的可获得性受到限制，希望这一原始 研究将促进广泛研究其他寄主-病原体相互作用中的水分调节，并从长远来看- 促进发展创新和广泛适用的措施，以控制不同类型的传染病 真核宿主，包括植物、动物和人类。