Role of insulin-dependent cortical fodrin/spectrin remodeling in glucose transporter 4 translocation in rat adipocytes
Role of insulin-dependent cortical fodrin/spectrin remodeling in glucose transporter 4 translocation in rat adipocytes
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DOI：
10.1091/mbc.e06-04-0278
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发表时间：
2006-10-01
影响因子：
3.3
通讯作者：
Pilch, Paul F.
中科院分区：
文献类型：
--
作者：
Liu, Libin;Jedrychowski, Mark P.;Pilch, Paul F.
Fodrin 或非红系血影蛋白是大鼠脂肪细胞皮质细胞骨架网络的丰富成分。胞质蛋白在静息细胞中呈高度点状分布，而胰岛素会导致胞质蛋白发生戏剧性的重塑，形成更分散的模式。胰岛素介导的肌动蛋白重塑程度低于胞质蛋白的重塑程度。我们发现，fodrin 与 t-可溶性 N-乙基马来酰亚胺敏感因子附着蛋白受体 (SNARE) 突触蛋白 4 相互作用，并且这种相互作用通过胰岛素刺激而增强，并通过先前的 latrunculin A 治疗而减弱。 Latrunculin A 破坏所有肌动蛋白丝，抑制葡萄糖转运蛋白 4 (GLUT4) 易位，并导致胞质蛋白部分从质膜重新分配到细胞质。相反，细胞松弛素 D 仅破坏短肌动蛋白丝信号，并且细胞松弛素 D 既不抑制脂肪细胞中的 GLUT4 易位，也不抑制胞质蛋白的重新分布。总之，我们的数据表明，胰岛素诱导胞因子-肌动蛋白网络的重塑，这是 GLUT4 储存囊泡与质膜融合所必需的，允许它们接触 t-SNARE 突触蛋白 4。
Fodrin or nonerythroid spectrin is an abundant component of the cortical cytoskeletal network in rat adipocytes. Fodrin has a highly punctate distribution in resting cells, and insulin causes a dramatic remodeling of fodrin to a more diffuse pattern. Insulin-mediated remodeling of actin occurs to a lesser extent than does that of fodrin. We show that fodrin interacts with the t-soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) syntaxin 4, and this interaction is increased by insulin stimulation and decreased by prior latrunculin A treatment. Latrunculin A disrupts all actin filaments, inhibits glucose transporter 4 (GLUT4) translocation, and causes fodrin to partially redistribute from the plasma membrane to the cytosol. In contrast, cytochalasin D disrupts only the short actin filament signal, and cytochalasin D neither inhibits GLUT4 translocation nor fodrin redistribution in adipocytes. Together, our data suggest that insulin induces remodeling of the fodrin-actin network, which is required for the fusion of GLUT4 storage vesicles with the plasma membrane by permitting their access to the t-SNARE syntaxin 4.