直接随机光学重构显微镜研究葡萄糖对INS-1细胞膜上突触融合蛋白1A的调控机制  

Mechanism Study of Glucose Regulation of Syntaxin 1A on INS-1 Cell Membranes by Direct Stochastic Optical Reconstruction Microscopy

作　　者：赵关芳 蔡明军[1,2] 李泓儒 邹天一 高婧 徐海娇[1] 王宏达[1,2,3] ZHAO Guan-Fang;CAI Ming-Jun;LI Hong-Ru;ZOU Tian-Yi;GAO Jing;XU Hai-Jiao;WANG Hong-Da(State Key Laboratory of Analytical Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;University of Science and Technology of China,Hefei 230026,China;Laboratory for Marine Biology and Biotechnology,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266237,China)

机构地区：[1]中国科学院长春应用化学研究所,电分析化学国家重点实验室,长春130022 [2]中国科学技术大学,合肥230026 [3]青岛海洋科学与技术国家实验室海洋生物学与生物技术实验室,青岛266237

出　　处：《分析化学》2023年第1期63-71,共9页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(Nos.21727816,21721003,22150003);中国科学院科学仪器研制项目(No.ZDKYYQ20220005)资助。

摘　　要：胰岛素的分泌受葡萄糖浓度的影响。突触融合蛋白1A(Syntaxin 1A,STX-1A)是可溶性N-乙基马来酰亚胺敏感因子附着蛋白受体(Soluble N-ethylmaleimide-sensitive factor attachment proteins receptor,SNARE)复合物的核心组件,对胰岛素分泌过程中胰岛素颗粒与细胞膜的锚定和融合至关重要。葡萄糖是否对STX-1A具有调控作用以及如何调控和影响胰岛素的释放的机制尚不清楚。本研究通过直接随机光学重构显微镜(Direct stochastic optical reconstruction microscopy,dSTORM)研究了葡萄糖浓度对INS-1细胞膜上的STX-1A的影响。研究发现,随着葡萄糖浓度升高,STX-1A在细胞膜上的表达量增加,STX-1A蛋白簇的密度和聚集程度也增加。但是,高浓度葡萄糖长时间刺激导致的糖毒性严重降低了细胞膜上STX-1A蛋白的表达量;同时,细胞膜上STX-1A蛋白簇的密度和聚集程度也显著降低。本研究将STX-1A在细胞膜上的表达和空间分布特征与胰岛素分泌细胞功能相关联,揭示了葡萄糖在分子水平上对STX-1A功能组织的调节作用,为研究SNAREs调节胰岛素释放的机制提供了新视角。The level and rate of insulin secretion are regulated by glucose concentration.Syntaxin 1A(STX-1A)is a core component of soluble N-ethylmaleimide-sensitive factor attachment proteins receptor(SNARE)complex and is essential for mediating the docking and fusion of insulin granules with cell membranes during insulin secretion.However,the mechanism of whether and how glucose regulates STX-1A to affect insulin release is still not well elucidated.To address this issue,the regulatory effect of glucose on STX-1A on INS-1 cell membranes was investigated by direct stochastic optical reconstruction microscopy(dSTORM).It was found that the elevated glucose concentration increased the expression of STX-1A on the cell membrane,and the density and aggregation of STX-1A protein clusters on the cell membrane were also increased.However,the glucotoxicity caused by chronic stimulation with high glucose concentration severely reduced the expression of STX-1A protein on the cell membrane,while the density and aggregation of STX-1A protein clusters on the cell membrane were also significantly reduced.By linking the expression and spatial distribution characteristics of STX-1A on cell membranes to insulin-secreting cell functions,the role of glucose in regulating the functional organization of STX-1A at the molecular level was revealed,which provided new insights into the mechanisms by which SNAREs regulate insulin release.

关 键 词：突触融合蛋白1A 可溶性N-乙基马来酰亚胺敏感因子附着蛋白受体复合物 直接随机光学重构显微镜 胰岛素 糖毒性 

分 类 号：R587.1[医药卫生—内分泌]