Novel roles of PDK4 in regulating mitochondrial protein phosphorylation, carbon flux and metabolic resilience

PDK4 在调节线粒体蛋白磷酸化、碳通量和代谢弹性中的新作用

• 批准号: 10444249
• 负责人: Paul A. Grimsrud
• 金额: $ 66.01万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-06 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10444249
• 关键词: ATP Synthesis Pathway; Acetyl Coenzyme A; Acute; Agreement; Animal Experiments; Attention; Binding; Bioenergetics; Body Composition; Carbon; Cardiac; Catabolism; Cells; Chemicals; Citric Acid Cycle; Consumption; Cues; Cultured Cells; Data; Diabetes Mellitus; Diagnostic; Energy Metabolism; Enzymes; Event; Exercise; Exposure to; Family; Fasting; Fatty Acids; Fatty acid glycerol esters; Gene Proteins; Generations; Genes; Genetic Engineering; Glucose; Glycolysis; Goals; Health Benefit; Heart; Heart Diseases; Human; Immunoprecipitation; In Vitro; Knock-out; Knockout Mice; Label; Laboratories; Ligands; Ligation; Lipids; Liver; Malates; Mass Spectrum Analysis; Mediating; Metabolic; Metabolic Diseases; Mitochondria; Mitochondrial Matrix; Mitochondrial Proteins; Modeling; Molecular Profiling; Mus; Muscle; Muscle Fibers; Myocardium; NADP; Nutrient; Oxidative Phosphorylation; PDH kinase; PDPK1 gene; Peptides; Peroxisome Proliferator-Activated Receptors; Phosphorylation; Physiological; Physiological Adaptation; Play; Process; Production; Proteins; Proteome; Proteomics; Pyruvate; Pyruvate Dehydrogenase Complex; Regimen; Regulation; Reporting; Respiratory physiology; Role; Series; Serine; Site; Skeletal Muscle; Soleus Muscle; Stress; Testing; Thinness; Time-restricted feeding; Tissues; Tracer; Up-Regulation; base; blood glucose regulation; diagnostic platform; enzyme activity; experimental study; flexibility; food restriction; in vivo; innovation; knockout animal; lead candidate; loss of function; malic enzyme; member; metabolomics; mouse model; novel; novel strategies; oligomycin sensitivity-conferring protein; overexpression; oxidation; phosphoproteomics; pyruvate dehydrogenase kinase 4; resilience; respiratory; response; stable isotope; stem; therapeutic target; tool; trafficking; transcription factor

ABSTRACT This project aims to understand of how mitochondrial carbon trafficking and bioenergetics are regulated by pyruvate dehydrogenase kinase 4 (PDK4), a protein that is highly responsive to nutrient and energetic cues and one that has received much attention as a potential therapeutic target. PDK4 is a member of a family of pyruvate dehydrogenase kinase enzymes (PDK1-4) that phosphorylate and inactive the mitochondrial pyruvate dehydrogenase complex (PDC). By converting pyruvate to acetyl-CoA, the PDC connects glycolysis to the tricarboxylic acid cycle (TCAC), which generates reducing equivalents needed for ATP synthesis. Notably, PDK4 is one of the most robustly induced genes/proteins in response to acute energy stresses–such as fasting, exercise and consumption of a high fat meal. PDK4 is also strongly induced by acute exposure to fatty acids and/or other ligands that activate the PPAR family of transcription factors. This remarkable level of nutrient/energy-induced regulation is unique to PDK4 (as compared with PDKs1-3), raising the possibility that PDK4 has distinct metabolic functions. The major conceptual innovation and central premise of this proposal stems from new and exciting evidence from our laboratory that PDK4 phosphorylates and regulates proteins beyond the PDC. Preliminary studies used mass spectrometry-based proteomics to assess the phospho- proteome of hearts and/or skeletal muscles from mice in which the PDK4 gene was overexpressed or ablated. In aggregate, the findings support a working model wherein PDK4 phosphorylates and regulates multiple mitochondrial enzymes and proteins in response to lipid stress. Accordingly, the project seeks to test hypothesis that PDK4 plays a central role in mediating lipid-induced phosphorylation of mitochondrial proteins beyond the PDC, which in turn modulates carbon trafficking and bioenergetics in manner that confers metabolic resilience. To test this hypothesis, we will combine gain- and loss-of-function mouse models with several state-of-the-art molecular profiling tools (mass spectrometry-based proteomics, phospho-proteomics, metabolomics and stable isotope metabolic flux analysis), a sophisticated mitochondrial diagnostics platform, and comprehensive physiological assessments to delineate the PDK4 interactome and its critical physiological functions.

抽象的 该项目旨在了解线粒体碳运输和生物能量学如何受到调节 丙酮酸脱氢酶激酶 4 (PDK4)，一种对营养和能量信号高度敏感的蛋白质， PDK4 是丙酮酸家族的一员，作为潜在的治疗靶点而受到广泛关注。 脱氢酶激酶 (PDK1-4)，使线粒体丙酮酸磷酸化并失活 脱氢酶复合物 (PDC) 通过将丙酮酸转化为乙酰辅酶A，PDC 将糖酵解与糖酵解连接起来。 三羧酸循环 (TCAC)，产生 ATP 合成所需的还原当量，尤其是 PDK4。 是响应急性能量压力（例如禁食、 急性暴露于脂肪酸也会强烈诱导运动和摄入高脂肪膳食。 和/或其他激活 PPAR 转录因子家族的配体。 营养/能量诱导的调节是 PDK4 所独有的（与 PDKs1-3 相比），这增加了以下可能性： PDK4具有独特的代谢功能，是该提案的主要概念创新和中心前提。 源自我们实验室的令人兴奋的新证据，即 PDK4 磷酸化和调节蛋白质 初步研究使用基于质谱的蛋白质组学来评估磷酸化。 PDK4 基因过度表达或消除的小鼠心脏和/或骨骼肌的蛋白质组。 总的来说，这些发现支持 PDK4 磷酸化和调节多种的工作模型 因此，该项目试图检验假设。 PDK4 在介导脂质诱导的线粒体蛋白磷酸化中发挥着核心作用 PDC，进而以赋予代谢弹性的方式调节碳运输和生物能量。 为了检验这一假设，我们将功能获得和丧失功能的小鼠模型与几种最先进的模型相结合 分子分析工具（基于质谱的蛋白质组学、磷酸化蛋白质组学、代谢组学和稳定 同位素代谢流分析），一个复杂的线粒体诊断平台，以及全面的 生理评估来描述 PDK4 相互作用组及其关键生理功能。