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.

项目摘要 结核病（TB）仍然是一个主要的健康问题，尤其是全球耐药性紧急情况 结核分枝杆菌（MTB）菌株。世界卫生组织估计几乎三分之一 目前，世界人口感染了MTB，使该芽孢杆菌成为最成功的病原体之一 地球。有助于MTB成功的关键因素是它在巨噬细胞内生存的能力，宿主 已经发展出捕获和杀死入侵微生物的能力的细胞。吞噬作用后，必须 不断监视并适当响应宿主的细菌活动，以建立避风港 在巨噬细胞的吞噬体中。 MTB在巨噬细胞内生存的过程很复杂，并且 仍然很了解。在此应用中，我们建议研究一种新型病毒机制 劫持干扰素伽玛激活的翻译抑制剂（步态），一种翻译调节机制 通常，宿主激酶在人类巨噬细胞中触发，以防止对干扰素伽玛的反应过多 （IFNγ），T细胞产生的一种促炎性细胞因子，以激活巨噬细胞中的抗菌活性。我们的 初步数据支持以下假设，即MTB的真核型Ser/Thr蛋白激酶G（PKNG） 影响60s-核糖体亚基蛋白L13A的磷酸化状态和glu/pro-tRNA 合成酶EPRS，以IFNγ独立的方式导致步态组装。特定的实验 目标1的目的是确定（i）响应分枝杆菌感染的步态组件动力学；（ii） PKNG在MTB诱导的步态组件中的作用和（iii）PKNG激酶活性对MTB内部生长的影响 人类主要巨噬细胞。此外，特定目标2中的实验旨在评估影响 MTB的PKNG诱导的步态组件在细胞核内存活率上。共同提出了这些 实验将阐明步态组装对MTB在人类中生存的生物学相关性 巨噬细胞，并通过其PKNG建立MTB能力的生物学重要性 集会。这种分子策略可能使MTB能够使巨噬细胞内环境较少抗 炎症和抗菌细菌，以促进其自身的生存。了解这样一个重要的病毒 机制可能有助于制定新的治疗策略，以促进我们的先天反MTB活动 免疫系统。