PI3 KINASE EFFECTORS IN INSULIN RESPONSIVE SYSTEMS

磷脂酰肌醇(PI)-3激酶是一个与之相关的酶家族 在控制不同的细胞过程中，包括膜蛋白 贩运、细胞迁移和细胞凋亡。这项提案的目标是 是研究PI-3激酶在膜上的作用机制(S) 蛋白质交易。已鉴定出一种紧密结合的蛋白质 对PI(3)P，但不对其他磷酸化肌苷，如PI(4)P， PI(4，5)P2，对其他酸性磷脂也没有影响。这种蛋白质被称为 EEA1，并包含与酵母蛋白中发现的类似的基序 与贩卖到空泡有关。初步结果表明 EEA1可能是胰岛素调节的GLUT4中的一个必要元件 内吞体系统的贩运。我们提出了四个具体目标：1) 为了检验无名指定义动力学的假设， EEA1与3‘端结合的特异性和结构基础 磷脂酰肌醇。2)为了检验EEA1函数是一个 胰岛素对供过于求的贩运起作用的必要因素。3)至 表征辅助肽的结构和一般功能 已发现与EEA1相互作用的基因。4)确定以下哪项 哺乳动物细胞中已知的PI-3激酶与EEA1相关 功能。

Phosphatidylinositol (PI)-3 kinases are a family of enzymes implicated in the control of diverse cellular processes, including membrane protein trafficking, cell migration and apoptosis. The goal of this proposal is to examine the mechanism(s) of action of PI-3 kinases on membrane protein trafficking. A protein has been identified that binds tightly to PI(3)P, but not to other phosphorylated inositides such as PI(4)P, PI(4,5)P2, nor to other acidic phospholipids. This protein is termed EEA1, and contains motifs similar to those found in yeast proteins implicated in trafficking to the vacuole. Preliminary results suggest that EEA1 may be a necessary element in insulin-regulated GLUT4 trafficking in the endosomal system. We propose four specific aims: 1) To test the hypothesis that the RING finger defines the kinetics, specificity and structural basis for the binding of EEA1 to 3' phosphoinositides. 2) To test the hypothesis that EEA1 function is a necessary element for insulin action on GLUT trafficking. 3) To characterize the structure and general function of accessory peptides that have been found to interact with EEA1. 4) To determine which of the known PI-3 kinases present in mammalian cells is relevant for EEA1 function.