The function of chemotactic signal transduction during colonization and disease

趋化信号转导在定植和疾病过程中的功能

• 批准号: 10686164
• 负责人: Karen M Ottemann
• 金额: $ 43万
• 依托单位: UNIVERSITY OF CALIFORNIA SANTA CRUZ
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-12-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10686164
• 关键词: Address; Affect; Antibiotics; Bacteria; Bacterial Infections; Behavior; Binding; Biochemical; Biological Assay; Cancer Etiology; Cancerous; Cessation of life; Chemoreceptors; Chemotaxis; Citrates; Collaborations; Complement; Crystallization; Crystallography; Cues; Data; Disease; Frequencies; Fumarates; Gastrointestinal tract structure; Genes; Genetic Transcription; Gland; Growth; Health; Helicobacter Infections; Helicobacter pylori; Immune; Incidence; Individual; Infection; Knowledge; Ligand Binding; Ligand Binding Domain; Ligands; Measures; Mediating; Metabolic; Metabolism; Methods; Microbe; Mission; Molecular Biology; Molecular Conformation; Mucous Membrane; Mus; Nature; Organism; Outcome; Pathogenesis; Pathogenicity; Persons; Physiology; Play; Population; Population Control; Population Dynamics; Process; Proteins; Public Health; Regulon; Research; Resistance; Resolution; Role; Series; Shapes; Signal Transduction; Signaling Molecule; Stomach; Structural Biologist; Structure; Testing; Therapeutic; Tissues; Ulcer; United States; United States National Institutes of Health; Waste Products; Work; burden of illness; colonization resistance; experimental study; extracellular; gene product; host-microbe interactions; in vivo; innovation; insight; malignant stomach neoplasm; mouse model; mutant; new therapeutic target; novel therapeutics; pathogen; pressure; prevent; receptor; response

Our proposed research focuses on defining the mechanism of action of the TlpC chemoreceptor in modulating colonization and pathogenesis of the ulcer-causing bacterium Helicobacter pylori. TlpC plays important and exciting roles in H. pylori pathogenesis, sensing host lactate and allowing H. pylori to use it to resist a previ- ously-unappreciated innate immune challenge, complement. The central tenet that guides this work is that un- derstanding chemotaxis signals will lend new insight into the nature of host-pathogen interactions. A gap re- mains, however in our understanding of how H. pylori uses lactate to promote complement resistance, how TlpC integrates lactate and other ligand sensing, and how and where TlpC-mediated sensing promotes in vivo growth. Continued existence of this gap prevents us from gaining a full understanding of H. pylori’s pathogenic mechanisms and, in the long term, creating new drugs to thwart these processes. Millions of people worldwide and in the U.S. are infected by H. pylori and suffer from its associated diseases—ulcers and gastric cancer. Gastric cancer is the fourth highest cause of cancer deaths worldwide. H. pylori is here to stay based on recent studies that show H. pylori incidence has stabilized in the developed world. Furthermore, current therapies to cure H. pylori infection fail with unacceptable frequency, e.g., recent estimates in the United States have found that 20-25% of infected individuals are not cured by the current therapeutic regime. New drug targets are des- perately needed. The specific objective of this application is to dissect TlpC signal transduction and the role of it and its sensed compounds in gastric colonization and disease. Our central hypothesis is that the TlpC- sensed compounds play fundamental roles in H. pylori colonization, and are sensed cooperatively using both subdomains of TlpC’s dCACHE ligand binding domain structure. Our hypothesis has been formulated from preliminary data using crystallization of TlpC, analyzing H. pylori ’s response to lactate and host complement, and determining the role of chemotaxis and TlpC in vivo. Our approach has three Aims, which combine H. py- lori molecular biology, mouse models, and high resolution protein crystallography. In Aim 1, we dissect the role of lactate in H. pylori colonization including how it promotes growth and complement resistance. In Aim 2, we determine how H. pylori TlpC integrates information from multiple ligands into a chemotaxis response. In Aim 3, we define how chemotaxis underlies in vivo population control. The proposed research is innovative in that it will create new knowledge about the functions of chemotaxis during bacterial pathogenesis, the role of comple- ment in the stomach, and high resolution information about how dCACHE ligand binding domains bind ligands. The proposed research is significant because both in our understanding of H. pylori pathogenesis but also for advancing our understanding of dCACHE ligand binding domains, the most common bacterial sensing module. The long-term outcomes generated by this research are likely to provide insights that will enable creation of new drugs against H. pylori-related disease.

我们提出的研究重点是确定TlpC化学受体在调节细胞凋亡中的作用机制。 引起溃疡的细菌幽门螺杆菌的定植和发病机制。TlpC发挥着重要作用， 在H中的精彩角色pylori发病机制，感知宿主乳酸并允许H.幽门螺杆菌来抵抗幽门螺杆菌 不被重视的先天免疫挑战，补体指导这项工作的核心原则是，联合国- 了解趋化性信号将使我们对宿主-病原体相互作用的本质有新的认识。一个缺口重新- 然而，在我们的理解如何H。幽门螺杆菌使用乳酸促进补体抵抗，如何 TlpC整合了乳酸和其他配体传感，以及TlpC介导的传感如何以及在何处在体内促进 增长这一差距的持续存在阻碍了我们对H的全面理解。幽门致病性 机制，并从长远来看，创造新的药物来阻止这些过程。全世界数百万人 而在美国，感染的是H幽门螺杆菌和遭受其相关的疾病-溃疡和胃癌。 胃癌是全球第四大癌症死亡原因。H.幽门螺杆菌在这里停留基于最近的 研究表明，H.幽门螺杆菌的发病率在发达国家已经稳定下来。此外，目前的治疗方法， 治愈H.幽门螺杆菌感染以不可接受的频率失败，例如，美国最近的估计发现， 20-25%的感染者不能通过目前的治疗方案治愈。新的药物靶点是- 非常需要。本申请的具体目的是剖析TlpC信号转导和TlpC在细胞内的作用。 它及其感测化合物在胃定植和疾病中的作用。我们的中心假设是TlpC- 感测化合物在H. pylori定植，并使用两者协同感知 TlpC的dCACHE配体结合结构域结构的亚结构域。我们的假设是从 初步数据使用TlpC的结晶，分析H.幽门对乳酸和宿主补体的反应， 并确定趋化性和TlpC在体内的作用。我们的方法有三个目标，其中联合收割机H。py- 洛里分子生物学、小鼠模型和高分辨率蛋白质晶体学。在目标1中，我们剖析了 乳酸含量在H.幽门螺杆菌定植，包括它如何促进生长和补体抵抗。在目标2中， 确定H. pylori TlpC将来自多个配体的信息整合到趋化反应中。在Aim中 3，我们定义了趋化性如何成为体内种群控制的基础。这项研究的创新之处在于， 将创造关于细菌致病过程中趋化性功能的新知识，复杂的， 胃中的膜，以及关于dCACHE配体结合结构域如何结合配体的高分辨率信息。 这项研究具有重要意义，因为我们对H.幽门螺杆菌的发病机制， 推进了我们对dCACHE配体结合结构域（最常见的细菌传感模块）的理解。 这项研究产生的长期结果可能会提供一些见解， 抗H.幽门相关疾病