Regulation and Function of hVps34 in Insulin Signaling

hVps34 在胰岛素信号传导中的调节和功能

• 批准号: 7569967
• 负责人: Jonathan M. Backer
• 金额: $ 29.14万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-06 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7569967
• 关键词: 1-Phosphatidylinositol 3-Kinase; 5' -AMP-activated protein kinase; 70-kDa Ribosomal Protein S6 Kinases; Address; Affect; Alcar; Amino Acids; Autophagocytosis; Binding; CISK; Catalytic Domain; Cells; Complex; Cultured Cells; Data; Diabetes Mellitus; Energy-Generating Resources; Event; Genetic; Glucose; Human; In Vitro; Insulin; Insulin Receptor; Link; Lipids; Mammalian Cell; Maps; Mass Spectrum Analysis; Measures; Mediating; Methods; Mutagenesis; Mutate; Nutrient; Phosphatidylinositols; Phosphopeptides; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphorylation Site; Phosphotransferases; Play; Protein Biosynthesis; Protein Kinase; Proteins; Public Health; Recycling; Regulation; Ribosomal Protein S6 Kinase; Role; Signal Transduction; Site; Small Interfering RNA; Stable Isotope Labeling; Starvation; System; Testing; Translations; United States; Yeasts; base; cost; detection of nutrient; embryonic stem cell; human FRAP1 protein; insulin signaling; knock-down; late endosome; mutant; novel; overexpression; receptor internalization; trafficking

Diabetes is a major public health problem in the United States and the world, with a huge societal cost in both human and financial terms. Phosphoinositide 3-kinases (PI 3-kinases) are lipid kinases that play an essential role in insulin action. While the function of p85/p110 PI 3-kinases in insulin responsive cells is well documented, the Class III PI 3-kinase, hVps34, also plays an significant role in insulin action. In this application, exciting new evidence is presented that links hVps34 to two nutrient sensing systems in mammalian cells: the AMP-activated Protein Kinase (AMPK), which regulates the utilization of alternative energy sources under low-nutrient conditions, and p70 S6-kinase (S6K), an key regulator of insulin- stimulated protein synthesis. Data presented in this application show that overexpression of hVps34 activates S6K, and that inhibition of hVps34 blocks insulin stimulation of S6K. In addition, hVps34 is inhibited by either glucose or amino acid starvation, conditions that also inhibit S6K. Finally, it is shown that hVps34 is inhibited by activation of AMPK. These novel data suggest that hVps34 plays an important role in nutrient sensing in mammalian cells; this is explored in four specific aims. Aim 1 examines the regulation of hVps34 by amino acids and glucose starvation, and will identify changes in hVps34 phosphorylation (using mass spectrometry-based methods) and in hVps34-associated proteins that occurs in starved cells. Aim 2 studies the role of AMPK in the inhibition of hVps34 in glucose-starved cells, and the mechanism of hVps34 regulation by AMPK. Aim 3 explores potential mechanisms of hVps34 signaling to S6K, including interactions with mTOR, Cdc42, and CISK. Finally, Aim 4 examines the function of the hVps34-associated protein beclin- 1. These studies explore the mechanism of beclin-1-hVps34 association, and the role of beclin-1 in hVps34- dependent vesicular trafficking and activation of S6K. Overall, these studies will have important implications for our understanding of the function and regulation of hVps34, and its role in insulin action and diabetes.

糖尿病是美国和世界上的一个主要公共卫生问题，在美国和世界上都有巨大的社会成本。 无论是人力还是财力磷脂酰肌醇3-激酶（PI 3-激酶）是一种脂质激酶， 在胰岛素作用中的重要作用。而p85/p110 PI 3-激酶在胰岛素敏感细胞中的功能较好， 据文献记载，III类PI 3-激酶hVps 34也在胰岛素作用中起重要作用。在这 应用，令人兴奋的新证据，提出了链接hVps 34两个营养传感系统， 哺乳动物细胞：AMP激活的蛋白激酶（AMPK），它调节替代的 低营养条件下的能量来源，以及p70 S6激酶（S6 K），胰岛素的关键调节因子， 刺激蛋白质合成。本申请中提供的数据显示hVps 34的过表达 激活S6 K，抑制hVps 34阻断胰岛素对S6 K的刺激。此外，hVps 34被抑制 通过葡萄糖或氨基酸饥饿，也抑制S6 K的条件。最后，它表明，hVps 34是 被AMPK的激活所抑制。这些新的数据表明，hVps 34在营养调控中起着重要作用。 在哺乳动物细胞中的传感;这是在四个具体的目标探索。目的1检查hVps 34的调节 通过氨基酸和葡萄糖饥饿，并将确定hVps 34磷酸化的变化（使用质量 基于光谱的方法）和在饥饿细胞中出现的hVps 34相关蛋白中。Aim 2研究 AMPK在葡萄糖饥饿细胞中抑制hVps 34的作用，以及hVps 34的作用机制 由AMPK监管。目的3探讨hVps 34信号转导S6 K的潜在机制，包括相互作用 mTOR，Cdc 42和CISK。最后，目的4检查hVps 34相关蛋白beclin的功能。 1.这些研究探讨了beclin-1与hVps 34结合的机制，以及beclin-1在hVps 34-hVps 34表达中的作用。 依赖性囊泡运输和S6 K活化。总的来说，这些研究将产生重要的影响， 为我们理解hVps 34的功能和调节，以及它在胰岛素作用和糖尿病中的作用。