Ras signaling in the activation of glucose transport by insulin.
Ras signaling in the activation of glucose transport by insulin.
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Ras 信号传导通过胰岛素激活葡萄糖转运。
DOI：
10.1073/pnas.91.11.4644
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发表时间：
1994
影响因子：
11.1
通讯作者：
LawrenceJr,JC
中科院分区：
文献类型：
--
作者：
Manchester,J;Kong,X;Lowry,OH;LawrenceJr,JC
一种涉及显微注射和微量分析的方法已经被开发来研究参与激素代谢控制的信号转导途径。我们应用这种策略来研究Ras信号在心肌细胞中胰岛素急性激活葡萄糖转运中的作用。通过测量在2-脱氧葡萄糖中孵育后单个细胞中2-脱氧葡萄糖6-磷酸（dGlc 6P）的初始积累速率来评估葡萄糖转运活性。胰岛素使dGlc 6P的蓄积增加3- 4倍，与其对葡萄糖转运的刺激作用一致。通过显微注射不可水解的GTP类似物，鸟苷5 '-[γ-硫代]三磷酸，其激活GTP结合蛋白的Ras超家族成员，dGlc 6P的积累增加数倍。注射活化的Ha-Ras蛋白也通过增加dGlc 6P来模拟胰岛素;而注射缺乏Ras功能所需的脂肪酰化的COOH末端位点的Ras蛋白则没有效果。向细胞中引入中和Ras抗体Y13-259减弱了胰岛素的作用。这些发现暗示Ras参与胰岛素对代谢的急性调节。
An approach involving microinjection and microanalysis has been developed to investigate signal-transduction pathways involved in the hormonal control of metabolism. We have applied this strategy to investigate the role of Ras signaling in the acute activation of glucose transport by insulin in cardiac myocytes. Glucose transport activity was assessed by measuring the initial rate of accumulation of 2-deoxyglucose 6-phosphate (dGlc6P) in individual cells after incubation in 2-deoxyglucose. Insulin increased accumulation of dGlc6P by 3- to 4-fold, consistent with its stimulatory effect on glucose transport. Accumulation of dGlc6P was increased severalfold by microinjecting the nonhydrolyzable GTP analogue, guanosine 5'-[gamma-thio]triphosphate, which activates members of the Ras superfamily of GTP-binding proteins. Injecting activated Ha-Ras protein also mimicked insulin by increasing dGlc6P; whereas, injecting a Ras protein lacking the COOH-terminal site of fatty acylation required for Ras function was without effect. Introducing the neutralizing Ras antibody Y13-259 into cells attenuated the effect of insulin. These findings implicate Ras in the acute regulation of metabolism by insulin.