Regulation and function of TBK1-mTOR crosstalk

TBK1-mTOR串扰的调控和功能

• 批准号: 10711161
• 负责人: Diane C. Fingar
• 金额: $ 40.84万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-19 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10711161
• 关键词: Adipocytes; Adipose tissue; Agonist; Alleles; Amino Acids; Anti-Inflammatory Agents; Attenuated; Biochemical; Catalytic Domain; Cell physiology; Cells; Communication; Complex; Cues; Cultured Cells; Dimerization; Disease; Double-Stranded RNA; EGF gene; FRAP1 gene; Genes; Goals; Growth Factor; Homeostasis; Hormones; Host Defense; Hyperglycemia; IL10 gene; Immune; Immune System Diseases; Immune response; Infection; Inflammation; Inflammatory; Insulin; Insulin Resistance; Interferon Type I; Interferon-beta; Interferons; Interleukin-10; Knock-in; Knock-out; Knowledge; Lead; Link; Macrophage; Malignant Neoplasms; Mediating; Mediator; Metabolic; Metabolic Diseases; Metabolism; Molecular; Mus; Myelogenous; Myeloid Cells; Non-Insulin-Dependent Diabetes Mellitus; Nutrient; Obese Mice; Obesity; Pathologic; Phagocytes; Phosphorylation; Phosphotransferases; Physiological; Physiology; Play; Poly I-C; Prevalence; Process; Production; Proteins; Regulation; Resistance; Role; Signal Transduction; Site; Stimulus; System; TANK-binding kinase 1; Testing; Therapeutic; Thinness; Viral; Work; blood glucose regulation; cytokine; defense response; diet-induced obesity; energy balance; glycemic control; immune function; improved; in vivo; insulin sensitivity; microbial; mimetics; pathogenic bacteria; pathogenic virus; response; tumorigenesis

Project Summary Cellular and organismal homeostasis requires integration of diverse local and systemic cues by cell signaling networks. The anabolic kinase mTOR (mechanistic target of rapamycin) integrates nutrient and growth factor availability, playing critical roles in cellular processes that modulate metabolism, tumorigenesis, and immune function. mTOR comprises the catalytic core of two functionally distinct, multi-subunit complexes, mTORC1 and mTORC2. Not surprisingly, aberrant mTOR function contributes to pathological states including obesity-linked type II diabetes, cancer, and immune disorders. Despite the physiological importance of mTOR, major gaps exist in our mechanistic understanding of mTOR regulation and function, particularly how mTOR communicates with other important regulatory systems to control cell and organismal physiology. Recent work from our lab provides the scientific premise for this proposal, which demonstrated that the non-canonical innate immune kinase TBK1 (TANK binding kinase 1) phosphorylates mTOR (on S2159) to increase mTORC1 and mTORC2 signaling upon cellular stimulation with innate immune agonists (e.g., the viral dsRNA mimetic poly(I:C); bacterial LPS), growth factors (EGF), or hormones (insulin) in cultured cells and in vivo (Bodur et al. 2018; Tooley et al. 2021). This work linked two physiologically important signaling systems not previously known to communicate. Classically, TBK1 responds to microbial-derived signals to initiate first-line host defense against viral and bacterial pathogens. These signals lead to phosphorylation and activation of TBK1, which drives ]production of type I interferons (e.g., IFNb) and IFN-stimulated genes (ISGs). More recent work implicates TBK1 in a broader range of functions including improved glycemic control during diet-induced obesity and tumorigenesis through poorly defined downstream mediators. We demonstrated recently that mice bearing a “TBK1 resistant”, phosphorylation deficient Mtor S2159A allele display systemic insulin resistance and hyperglycemia in the diet-induced obese but not the lean state (Bodur et al. 2022). Macrophages and adipose tissue from these mice display reduced expression of IFNb and the anti-inflammatory ISG IL-10 as well as elevated expression of pro-inflammatory cytokines (Bodur et al. 2022). The overarching goal of this application is to elucidate the regulation and function of TBK1-mTOR crosstalk in cells and in vivo. We will employ biochemical, cellular, and molecular approaches to better define how TBK1 promotes mTORC1 and mTORC2 signaling in the absence of microbial-derived signals (Aim 1). We will also investigate how TBK1- mTOR signaling protects against insulin resistance, hyperglycemia, and inflammation in the diet-induced obese but not lean state by studying mice in vivo and primary cells in culture (Aim 2). This project will not only elucidate basic mechanisms underlying control of TBK1-mTOR signaling but will also advance our knowledge of mechanisms that integrate innate immune and metabolic signals to protect against obesity-linked metabolic disease, in particular type II diabetes, a disease with growing and alarming prevalence worldwide.

项目概要 细胞和有机体的稳态需要细胞整合不同的局部和全身信号 信令网络。合成代谢激酶 mTOR（雷帕霉素的机制靶点）整合了营养和 生长因子的可用性，在调节新陈代谢、肿瘤发生、 和免疫功能。 mTOR 包含两个功能不同的多亚基复合物的催化核心， mTORC1 和 mTORC2。毫不奇怪，异常的 mTOR 功能会导致病理状态，包括 与肥胖相关的 II 型糖尿病、癌症和免疫疾病。尽管 mTOR 具有生理重要性， 我们对 mTOR 调控和功能的机制理解存在重大差距，特别是 mTOR 如何 与其他重要的调节系统通信以控制细胞和有机体生理学。最近的工作 我们实验室的研究为这一提议提供了科学前提，证明了非规范的 先天免疫激酶 TBK1（TANK 结合激酶 1）磷酸化 mTOR（位于 S2159）以增加 mTORC1 和 mTORC2 信号在先天免疫激动剂（例如病毒 dsRNA 模拟物）细胞刺激后 聚(I:C)；培养细胞和体内的细菌 LPS）、生长因子（EGF）或激素（胰岛素）（Bodur 等人，2015）。 2018；图利等人。 2021）。这项工作将两个生理上重要的信号系统联系起来，这是以前从未有过的 已知可以沟通。传统上，TBK1 响应微生物衍生的信号来启动一线宿主 防御病毒和细菌病原体。这些信号导致 TBK1 磷酸化和激活， 它驱动 I 型干扰素（例如 IFNb）和 IFN 刺激基因（ISG）的产生。更多最近的工作 表明 TBK1 具有更广泛的功能，包括改善饮食诱导期间的血糖控制 通过不明确的下游介质来影响肥胖和肿瘤发生。我们最近证明了小鼠 具有“TBK1 抗性”、磷酸化缺陷的 Mtor S2159A 等位基因显示全身胰岛素抵抗 饮食引起的肥胖而非瘦状态会出现高血糖（Bodur et al. 2022）。巨噬细胞和 这些小鼠的脂肪组织显示 IFNb 和抗炎 ISG IL-10 的表达降低，如 以及促炎细胞因子表达升高（Bodur 等人，2022）。本次活动的总体目标是 该应用的目的是阐明TBK1-mTOR串扰在细胞和体内的调节和功能。我们将 采用生化、细胞和分子方法来更好地确定 TBK1 如何促进 mTORC1 和 在没有微生物衍生信号的情况下的 mTORC2 信号传导（目标 1）。我们还将研究 TBK1- mTOR 信号传导可预防饮食引起的肥胖症中的胰岛素抵抗、高血糖和炎症 但不是通过研究体内小鼠和培养物中的原代细胞来达到瘦状态（目标 2）。该项目不仅将 阐明 TBK1-mTOR 信号传导控制的基本机制，同时也将增进我们的知识 整合先天免疫和代谢信号以防止肥胖相关代谢的机制 疾病，特别是 II 型糖尿病，这种疾病在世界范围内的患病率不断上升且令人震惊。