title: Super-resolution microscopy reveals the insulin-resistance-regulated reorganization of GLUT4 on plasma membranes.
abstract: GLUT4 (also known as SLC2A4) is essential for glucose uptake in skeletal muscles and adipocytes, which play central roles in whole-body glucose metabolism. Here, using direct stochastic optical reconstruction microscopy (dSTORM) to investigate the characteristics of plasma-membrane-fused GLUT4 at the single-molecule level, we have demonstrated that insulin and insulin resistance regulate the spatial organization of GLUT4 in adipocytes. Stimulation with insulin shifted the balance of GLUT4 on the plasma membrane toward a more dispersed configuration. In contrast, insulin resistance induced a more clustered distribution of GLUT4 and increased the mean number of molecules per cluster. Furthermore, our data demonstrate that the F5QQI motif and lipid rafts mediate the maintenance of GLUT4 clusters on the plasma membrane. Mutation of F5QQI (F5QQA-GLUT4) induced a more clustered distribution of GLUT4; moreover, destruction of lipid rafts in adipocytes expressing F5QQA-GLUT4 dramatically decreased the percentage of large clusters and the mean number of molecules per cluster. In conclusion, our data clarify the effects of insulin stimulation or insulin resistance on GLUT4 reorganization on the plasma membrane and reveal new pathogenic mechanisms of insulin resistance.
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, P.R. China.|Graduate University of Chinese Academy of Sciences, Beijing 100049, P.R. China.
authors.forename: Lan
authors.initials: L
authors.lastname: Gao
authors.affiliation: Graduate University of Chinese Academy of Sciences, Beijing 100049, P.R. China.|State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilil 130022, P.R. China.
authors.forename: Junling
authors.initials: J
authors.lastname: Chen
authors.affiliation: Graduate University of Chinese Academy of Sciences, Beijing 100049, P.R. China.|State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilil 130022, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilil 130022, P.R. China xiong.wenyong@mail.kib.ac.cn hdwang@ciac.ac.cn.
authors.forename: Hongda
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, P.R. China xiong.wenyong@mail.kib.ac.cn hdwang@ciac.ac.cn.
authors.forename: Wenyong
authors.identifier: 0000-0001-9174-3667
authors.initials: W
authors.lastname: Xiong
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000378:metabolism; D020816:Amino Acid Motifs; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D051275:Glucose Transporter Type 4 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D021962:Membrane Microdomains / Q000378:metabolism; D051379:Mice; D008853:Microscopy / Q000379:methods*; D009154:Mutation / Q000235:genetics; D013269:Stochastic Processes
chemical_list: D051275:Glucose Transporter Type 4; D007328:Insulin
keywords: Direct stochastic optical reconstruction microscopy; GLUT4; Insulin resistance; Membrane protein; dSTORM