PI3 KINASE EFFECTORS IN INSULIN RESPONSIVE SYSTEMS

磷脂酰肌醇（PI）-3激酶是一个家族的酶参与 在控制不同的细胞过程，包括膜蛋白 运输、细胞迁移和凋亡。 这项提案的目的是 是检查PI-3激酶对膜的作用机制， 蛋白质运输 一种蛋白质已经被鉴定出 对PI（3）P，但不对其它磷酸化肌醇如PI（4）P， PI（4，5）P2，也不与其它酸性磷脂结合。 这种蛋白质被称为 EEA 1，并含有类似于酵母蛋白中发现的基序 与运输到空泡有关初步结果表明 EEA 1可能是胰岛素调节的GLUT 4中的一个必要元素， 内体系统中的运输。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， EEA 1与3'端结合的特异性和结构基础 磷酸肌醇。2)为了检验EEA 1功能是一种 胰岛素对GLUT运输起作用的必要因素。3)到 表征辅助肽的结构和一般功能 已经发现与EEA 1相互作用。4)以确定哪个 哺乳动物细胞中存在的已知PI-3激酶与EEA 1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.