Study on the mechanism of insulin stimulation of glucose transport

胰岛素刺激葡萄糖转运的机制研究

• 批准号: 09671021
• 负责人: SHIBATA Hiroshi
• 金额: $ 2.37万
• 依托单位: Gunma University, Institute For Molecular and Cellular Regulation
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09671021/
• 关键词: insulin; glucose transporter; GTP-binding protein; Rab4; syntaxin4; dynamin; グリコーストランスポーター

In the present study, we calrified that insulin stimulated guanine nucleotide exchange on Rab4 in rat adipocytes. This insulin action was markedly attenuated with phosphatidylinositol (PI) 3-kinase inhibitors, wortmannin or LY294002, suggesting that Pl 3-kinase may be an essential signaling component for insulin activation of Rab4. Additionally, we investigated the interaction of Rab4 with syntaxin4, a t-SNARE protein implicated in the insulin-induced exocytic fusion of the GLUT4-containing vesicle with the plasma membrane. Rab4 and syntaxin4 were co-immunoprecipitated from the homogenate of rat adipocytes. The interaction of the two proteins were attenuated by pretreatment of the cells with insulin but enhanced with GTPgammaS.GTP-binding proteins regulate both exocytotic and endocytotic steps of GLUT4-containing vesicles in rat adipocytes. Furthermore, we demonstrated that protein kinase Cgamma may be the upstream regulator of the insulin action on Rab4.We also clarified that dynamin is a regulatory GTPase of GLUT4 endocytosis by using mutant dynamin expressed in CHO cells.

在本研究中，我们证实胰岛素刺激大鼠脂肪细胞中 Rab4 上的鸟嘌呤核苷酸交换。磷脂酰肌醇 (PI) 3-激酶抑制剂、渥曼青霉素或 LY294002 显着减弱了这种胰岛素作用，表明 PI 3-激酶可能是 Rab4 胰岛素激活的重要信号成分。此外，我们研究了 Rab4 与 syntaxin4 的相互作用，syntaxin4 是一种 t-SNARE 蛋白，参与胰岛素诱导的含有 GLUT4 的囊泡与质膜的胞吐融合。 Rab4 和 Syntaxin4 从大鼠脂肪细胞匀浆中进行免疫共沉淀。用胰岛素预处理细胞可以减弱两种蛋白的相互作用，但用 GTPgammaS 可以增强这种相互作用。GTP 结合蛋白调节大鼠脂肪细胞中含有 GLUT4 的囊泡的胞吐和胞吞步骤。此外，我们证明蛋白激酶Cgamma可能是Rab4上胰岛素作用的上游调节因子。我们还通过使用CHO细胞中表达的突变动力蛋白阐明了动力蛋白是GLUT4内吞作用的调节GTP酶。

项目成果

Shibata, H.et al.: "Insulin stimulates guanine nucleotide exchange on Rab4 via a wortmannin-sensitive signaling pathway in rat adipocytes." J.Biol.Chem.272. 14542-1454,6 (1997)

Shibata, H.等人：“胰岛素通过大鼠脂肪细胞中的渥曼青霉素敏感信号通路刺激 Rab4 上的鸟嘌呤核苷酸交换。”

Shibata,H.他: "Insulin stimulates guanine mucleotide exchange on Rab4 via a wortmannin-sensitive signaling pathway in rat adipocytes." J,Biol.Chem.272. 14542-14546 (1997)

Shibata, H. 等人：“胰岛素通过大鼠脂肪细胞中的渥曼青霉素敏感信号通路刺激 Rab4 上的鸟嘌呤核苷酸交换。”J,Biol.Chem.272 (1997)。

柴田 宏: "インスリン作用とグルコーストランスポーター" Molecular Medicine. 35. 32-42 (1998)

Hiroshi Shibata：“胰岛素作用和葡萄糖转运蛋白”分子医学 35. 32-42 (1998)。

Shibata, H.: "Insuilon action and glucose transporter" Molecular Medicine. 35. 32-42 (1998)

Shibata, H.：“胰岛素作用和葡萄糖转运蛋白”分子医学。

Omata, W., Shibata, H., Suzuki, Y., Tanaka, S., Suzuki, T., Takata, K.and Kojima, I.: "Subcellular distribution of GLUT4 in chinese hamster ovary cells oveexpressing mutant dynamin : Evidence that dynamin is a regulatory GTPase in GLUT4 endocytosis." Bioc

Omata, W.、Shibata, H.、Suzuki, Y.、Tanaka, S.、Suzuki, T.、Takata, K. 和 Kojima, I.：“过表达突变动力的中国仓鼠卵巢细胞中 GLUT4 的亚细胞分布：证据