INSULIN REGULATION OF THE ADIPOCYTE GLUCOSE TRANSPORTER

胰岛素对脂肪细胞葡萄糖转运蛋白的调节

• 批准号: 3227346
• 负责人: GUSTAV E. LIENHARD
• 金额: $ 16.64万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 1979
• 资助国家: 美国
• 起止时间: 1979-04-01 至 1992-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3227346
• 关键词: acylation; adipocytes; affinity chromatography; antibody; cell membrane; gel electrophoresis; glucose transport; glycosylation; hormone regulation /control mechanism; immunochemistry; immunoelectron microscopy; insulin; insulin receptor; laboratory rabbit; membrane permeability; membrane proteins; phosphorylation; tissue /cell culture; transport proteins

Insulin stimulates the rate of glucose transport into adipocytes 10 to 15-fold within ten minutes. This remarkable stimulation is due at least in part to the translocation of glucose transporters from within the cell to the plasma membrane. The long-term objective is to elucidate at the molecular level how insulin causes this translocation of transporters. The specific aims for the coming grant period are as follows. (1) We have recently developed an immunoadsorption method for the purification of vesicles that contain the insulin-responsive, intracellular glucose transporters. The cellular organelle that contains these transporters will be identified by biochemical and electron microscopic methods. The composition, arrangement, and function of the polypeptides in these vesicles will be determined. (2) The quantitative contribution that the translocation of transporters to the plasma membranes makes to the overall stimulation of cellular glucose transport by insulin will be assessed. (3) The question of whether the glucose transporter is rapidly recycling between the plasma membrane and the endosomal compartment will be answered. If recycling is occurring, the site of insulin action on the kinetics will be ascertained. To achieve aims (2) and (3), a method for labeling the extracelllular domain of the transporter with a membrane-impermeant reagent will be developed. (4) The nature of the signal between the insulin receptor and the transporter will be investigated. Possible roles for covalent modification of the transporter, or of a transporter-associated protein, and for an intracellular mediator will be examined. (5) A major effort will be made to develop a cell-free system in which the insulin- stimulated translocation of transporters occurs. if this succeeds, the components of the system will be purified. All these studies will be conducted with the 3T3-L1 adipocyte. The results of this project will contribute to our knowledge of the mechanism of insulin action. They will therefore be of relevance to diabetes, since this disease is due to insulin deficiency or insensitivity.

胰岛素刺激葡萄糖转运到脂肪细胞的速率10 10分钟内翻了15倍 这种显著的刺激是由于 至少部分是由于葡萄糖转运蛋白从 细胞内的细胞膜。 长期目标 就是在分子水平上阐明胰岛素是如何导致 转运蛋白易位。 未来的具体目标 补助期如下。 (1)我们最近开发了一种 用于纯化囊泡的免疫吸附方法， 含有胰岛素敏感的细胞内葡萄糖转运蛋白。 包含这些转运蛋白的细胞器将 通过生物化学和电子显微镜方法鉴定。 的 多肽的组成、排列和功能， 将测定这些囊泡。 (2)定量 转运蛋白转运至血浆的作用 膜使细胞葡萄糖的整体刺激 将评估胰岛素的转运。 (3)的问题 葡萄糖转运蛋白在血浆和血浆之间快速循环 膜和内体隔室将被回答。 如果 循环正在发生，胰岛素作用于动力学的位点 将被确定。 为了实现目的（2）和（3），提供了一种方法， 将转运蛋白的细胞外结构域用 将开发膜不渗透试剂。 (4)性质 胰岛素受体和转运蛋白之间的信号 追究 共价修饰的可能作用 转运蛋白或转运蛋白相关蛋白，以及 将检查细胞内介质。 (5)一项重大努力将 开发一个无细胞系统，在这个系统中，胰岛素- 发生转运蛋白的受刺激易位。 如果这成功了， 系统的组分将被纯化。 所有这些研究 将使用3 T3-L1脂肪细胞进行。 的结果 该项目将有助于我们了解 胰岛素作用。 因此，它们与糖尿病有关， 因为这种疾病是由于胰岛素缺乏或不敏感。