GAIT complex formation and Mycobacterium tuberculosis

步态复合体的形成和结核分枝杆菌

• 批准号: 10195661
• 负责人: Liem Duy Nguyen
• 金额: $ 24.15万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10195661
• 关键词: Affect; Amino Acyl-tRNA Synthetases; Anti-Inflammatory Agents; Antibodies; Antimycobacterial Agents; Bacillus; Binding; Biological; CCL11 gene; CCL22 gene; CCL25 gene; CDK5 gene; CDK6-associated protein p18; CXCL13 gene; Cell Line; Cells; Ceruloplasmin; Complement; Complex; Cyclic GMP-Dependent Protein Kinases; Data; Detection; Drug resistance in tuberculosis; Elements; Environment; Etiology; Exposure to; Genus Mycobacterium; Goals; Growth; Health; Human; Immune response; Immune system; Immunoprecipitation; Infection; Inflammation; Inflammatory; Interferon Type II; Interferon-alpha; Invaded; Kinetics; Macrophage Activation; Macrophage Colony-Stimulating Factor; Measures; Mediating; Messenger RNA; Microbe; Modeling; Molecular; Monitor; Mycobacterium Infections; Mycobacterium bovis; Mycobacterium tuberculosis; Mycobacterium tuberculosis H37Rv; Natural Immunity; Outcome; Pathogenesis; Pathogenicity; Peripheral Blood Mononuclear Cell; Phagocytosis; Phagosomes; Pharmacologic Substance; Phosphorylation; Phosphotransferases; Planet Earth; Population; Process; Protein Inhibition; Protein Kinase; Protein Subunits; Proteins; Reaction; Ribosomal Proteins; Ribosomes; Role; System; T-Lymphocyte; Testing; Translations; Tuberculosis; U937 Cells; Untranslated Regions; VEGFA gene; Virulence; Western Blotting; World Health Organization; antimicrobial; bactericide; cGMP-dependent protein kinase Ibeta; chemokine; cytokine; design; experimental study; inhibitor/antagonist; macrophage; mimetics; monocyte; mutant; mycobacterial; novel; novel therapeutic intervention; p38 Mitogen Activated Protein Kinase; pathogen; prevent; prolylglutamic acid; receptor; resistance mechanism; response; success

PROJECT SUMMARY Tuberculosis (TB) remains a major health concern, especially with the global emergence of drug resistant Mycobacterium tuberculosis (Mtb) strains. The World Health Organization estimated that nearly one third of the world's population is currently infected with Mtb, making this bacillus one of the most successful pathogens on earth. A key factor that contributes to the success of Mtb is its ability to survive inside macrophage, the host cell that has evolved the ability to capture and kill invading microbes. Following phagocytosis, Mtb must continuously monitor and appropriately respond to host bactericidal activities in order to establish a safe haven inside the macrophage's phagosome. The process by which Mtb survive inside macrophages is complex and still poorly understood. In this application, we propose to study a novel virulence mechanism by which Mtb hijacks the Interferon Gamma Activated Inhibitor of Translation (GAIT), a translational regulatory mechanism normally triggered in human macrophages by host kinases to prevent excessive reactions to interferon-gamma (IFNγ), a pro-inflammatory cytokine produced by T cells to activate antimicrobial activities in macrophages. Our preliminary data support the hypothesis that the eukaryotic-type Ser/Thr protein kinase G (PknG) from Mtb affects the phosphorylation status of the 60S-ribosomal subunit protein L13a, and the Glu/Pro-tRNA synthetase, EPRS, leading to the assembly of GAIT in an IFNγ-independent manner. Experiments in Specific Aim 1 are aimed to determine (i) the kinetics of GAIT assembly in response to mycobacterial infection, (ii) the role of PknG in Mtb-induced GAIT assembly and (iii) the impact of PknG kinase activity on Mtb growth inside human primary macrophages. Furthermore, experiments in Specific Aim 2 are designed to assess the impact of Mtb's PknG-induced GAIT assembly on the bacillus' intracellular survival. Together, these proposed experiments will elucidate the biological relevance of GAIT assembly for Mtb's survival in human macrophages, and establish the biological importance of Mtb's ability, through its PknG, to hijack GAIT assembly. This molecular tactic may allow Mtb to render the macrophage intracellular environment less anti- inflammatory and antimycobacterial, to promote its own survival. Understanding such an important virulence mechanism may help to develop novel therapeutic strategies that boost the innate anti-Mtb activities of our immune system.

项目概要 结核病 (TB) 仍然是一个主要的健康问题，特别是随着全球耐药性的出现 结核分枝杆菌 (Mtb) 菌株。世界卫生组织估计，近三分之一的人 目前，全世界人口都感染了 Mtb，这使得这种杆菌成为人类最成功的病原体之一。 地球。 Mtb 成功的一个关键因素是其在宿主巨噬细胞内生存的能力 细胞已经进化出捕获和杀死入侵微生物的能力。吞噬作用后，Mtb 必须 持续监测并适当应对宿主的杀菌活动，以建立安全港 位于巨噬细胞的吞噬体内。 Mtb 在巨噬细胞内的生存过程非常复杂 仍然知之甚少。在本申请中，我们建议研究一种新的毒力机制，通过该机制，结核分枝杆菌 劫持干扰素伽玛激活翻译抑制剂（GAIT），一种翻译调节机制 通常由宿主激酶在人类巨噬细胞中触发，以防止对干扰素-γ的过度反应 (IFNγ)，一种由 T 细胞产生的促炎细胞因子，可激活巨噬细胞的抗菌活性。我们的 初步数据支持这样的假设：来自 Mtb 的真核型 Ser/Thr 蛋白激酶 G (PknG) 影响 60S-核糖体亚基蛋白 L13a 和 Glu/Pro-tRNA 的磷酸化状态 合成酶 EPRS，导致 GAIT 以不依赖 IFNγ 的方式组装。具体实验 目标 1 旨在确定 (i) 响应分枝杆菌感染的 GAIT 组装动力学，(ii) PknG 在 Mtb 诱导的 GAIT 组装中的作用以及 (iii) PknG 激酶活性对 Mtb 内部生长的影响 人类初级巨噬细胞。此外，具体目标 2 中的实验旨在评估影响 Mtb PknG 诱导的 GAIT 组装对芽孢杆菌细胞内存活的影响。这些提议共同 实验将阐明步态组装与结核分枝杆菌在人类中生存的生物学相关性 巨噬细胞，并确定 Mtb 通过其 PknG 劫持 GAIT 能力的生物学重要性 集会。这种分子策略可能会让 Mtb 降低巨噬细胞的细胞内环境的抗性。 具有抗炎和抗分枝杆菌作用，促进其自身生存。了解如此重要的毒力 机制可能有助于开发新的治疗策略，增强我们的先天抗 Mtb 活性 免疫系统。