Syntaxin 1 interacts with the L_D subtype of voltage-gated Ca<SUP>2+</SUP> channels in pancreatic β cells

作     者：Yang, SN Larsson, O Bränström, R Bertorello, AM Leibiger, B Leibiger, IB Moede, T Köhler, M Meister, B Berggren, PO 

作者机构：Karolinska Hosp Karolinska Inst Rolf Luft Ctr Diabet Res Dept Mol Med S-17176 Stockholm Sweden Karolinska Hosp Karolinska Inst Dept Neurosci S-17176 Stockholm Sweden 

出 版 物：《PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA》 (美国国家科学院汇刊)

年 卷 期：1999年第96卷第18期

页      面：10164-10169页

核心收录：

学科分类：07[理学] 08[工学] 

主　　题：抗体 单克隆/药理学 抗原 表面/免疫学 抗原 表面/分离和提纯 抗原 表面/代谢 钙/代谢 钙通道/遗传学 钙通道/分离和提纯 钙通道/生理学 钙通道 L型 细胞膜/生理学 细胞膜/超微结构 离心法 梯密度 胞吐作用/生理学 绿色荧光蛋白质类 胰岛/生理学 发光蛋白质类/遗传学 大分子物质 小鼠 肥胖 神经组织蛋白质类/免疫学 神经组织蛋白质类/分离和提纯 神经组织蛋白质类/代谢 膜片钳术 重组融合蛋白质类/代谢 突触融合蛋白质1 微管蛋白/免疫学 微管蛋白/生理学 动物 小鼠 

摘      要：Interaction of syntaxin 1 with the alpha(1D) subunit of the voltage-gated L type Ca2+ channel was investigated in the pancreatic beta cell, Coexpression of the enhanced green fluorescent protein-linked alpha(1D) subunit with the enhanced blue fluorescent protein-linked syntaxin 1 and Western blot analysis together with subcellular fractionation demonstrated that the alpha(1D) subunit and syntaxin 1 were colocalized in the plasma membrane. Furthermore, the alpha(1D) subunit was coimmunoprecipitated efficiently by a polyclonal antibody against syntaxin 1, Syntaxin 1 also played a central role in the modulation of L type Ca2+ channel activity because there was a faster Ca2+ current run-down in cells incubated with antisyntaxin 1 compared with controls. In parallel, antisyntaxin 1 markedly reduced insulin release in both intact and permeabilized cells, subsequent to depolarization with K+ or exposure to high Ca2+, Exchanging Ca2+ for Ba2+ abolished the effect of antisyntaxin 1 on both Ca2+ channel activity and insulin exocytosis, Moreover, antisyntaxin 1 had no significant effects on Ca2+-independent insulin release trigged by hypertonic stimulation, This suggests that there is a structure-function relationship between the air, subunit of the L type Ca2+ channel and the exocytotic machinery in the pancreatic beta cell.