SIGNAL TRANSDUCT OF INSULINS METABOLIC EFFECT

胰岛素刺激葡萄糖向脂肪和肌肉的转运增加 通过引起胰岛素反应性葡萄糖的移位 在一些实施方案中，GLUT 4是从细胞内池到质膜的转运蛋白。 胰岛素的靶组织不能以这种方式应答， 非胰岛素依赖型糖尿病的主要缺陷之一。 然而，导致GLUT 4易位的信号传导事件很少， 明白本提案的重点是调查 触发GLUT 4的细胞内胰岛素信号通路 易位阐明胰岛素刺激 葡萄糖转运可以确定新的潜在靶点， 干预胰岛素抵抗状态。实验将是 在3 T3-L1脂肪细胞中进行，其中胰岛素刺激的GLUT 4 易位可以在单个细胞的基础上进行评估， 用抗GLUT 4抗体进行免疫荧光染色。显微注射 单个活细胞将被用来提供各种试剂， 激活或抑制特异性细胞内分子， 参与胰岛素的作用。几乎可以输送任何类型的试剂 例如抗体、肽和重组蛋白。那里 有许多潜在的信号分子将被研究 利用该系统，包括胰岛素受体的底物，p21 ras， Raf、MEK和ERK Ser/Thr激酶，磷脂酰肌醇3-激酶和 Rab小GTP结合蛋白。

Insulin stimulates increased glucose transport into adipose and muscle tissue by causing translocation of the insulin responsive glucose transporter (GLUT4) from an intracellular pool to the plasma membrane. The inability of insulin's target tissues to respond in this manner is one of the primary defects in noninsulin-dependent diabetes mellitus. However, the signaling events that lead to GLUT4 translocation are poorly understood. The focus of this proposal is to investigate the intracellular insulin signaling pathways that trigger GLUT4 translocation. Elucidation of the mechanism whereby insulin stimulates glucose transport may identify new potential targets for therapeutic intervention in insulin resistant states. The experiments will be performed in 3T3-L1 adipocytes, in which insulin-stimulated GLUT4 translocation can be assessed on a single cell basis by immunofluorescence staining with anti GLUT4 antibodies. Microinjection of single living cells will be used to deliver various reagents to activate or inactivate specific intracellular molecules that may be involved in insulin action. Nearly any type of reagent can be delivered in this way, such as antibodies, peptides and recombinant proteins. There are many potentially involved signaling molecules that will be studied with this system, including substrates of the insulin receptor, p21 ras, the Raf, MEK and ERK Ser/Thr kinases, phosphatidylinositol 3-kinase and Rab small GTP-binding proteins.