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: 7195113
• 负责人: Jonathan M. Backer
• 金额: $ 29.74万
• 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 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7195113
• 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; Class; Complex; Condition; 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; Personal Satisfaction; Phosphatidylinositols; Phosphopeptides; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphorylation Site; Phosphotransferases; Play; Protein Biosynthesis; Protein Kinase; Protein Overexpression; 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; receptor internalization; trafficking

DESCRIPTION (provided by applicant): 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 a 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), a 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.

描述(申请人提供)：糖尿病是美国和世界上一个主要的公共卫生问题，在人力和经济方面都造成了巨大的社会成本。肌醇磷脂 3-激酶(PI-3-Kinase)是一类在胰岛素作用中起重要作用的脂蛋白激酶。虽然p85/p110PI 3-激酶在胰岛素反应细胞中的功能已被充分证实，但III型PI 3-激酶，hVps34，也在胰岛素作用中发挥重要作用。在这一应用中，出现了令人兴奋的新证据，将hVps34与哺乳动物细胞中的两个营养传感系统联系起来：调节低营养条件下替代能源利用的AMP激活蛋白激酶(AMPK)和胰岛素刺激蛋白质合成的关键调节因子p70 S6-K(S6K)。本申请中提供的数据显示，hVps34的过表达激活了S6K，而抑制hVps34则阻断了S6K的胰岛素刺激。此外，葡萄糖或氨基酸饥饿也会抑制S6K，hVps34也会受到抑制。结果表明，AMPK的激活抑制了hVps34的表达。这些新的数据表明，hVps34在哺乳动物细胞的营养感知中发挥着重要作用；这是从四个特定的目的来探索的。目的1检测氨基酸和葡萄糖饥饿对hVps34的调节，并将确定饥饿细胞中hVps34磷酸化(使用基于质谱学的方法)和hVps34相关蛋白的变化。目的2研究AMPK在抑制葡萄糖饥饿细胞hVps34中的作用，以及AMPK调节hVps34的机制。目的3探讨hVps34信号转导S6K的可能机制，包括与mTOR、CDC42和Cisk的相互作用。最后，Aim 4研究了hVps34相关蛋白beclin-1的功能。这些研究探索了beclin-1-hVps34结合的机制，以及beclin-1在hVps34依赖的囊泡运输和激活S6K中的作用。总体而言，这些研究将对我们理解hVps34的功能和调节，以及它在胰岛素作用和糖尿病中的作用具有重要意义。