title: Down-regulation of Kir6.2 affects calcium influx and insulin secretion in HIT-T15 cells.
abstract: In pancreatic beta cells, ATP-sensitive potassium (K(ATP)) channels are metabolic sensors that couple cell metabolism to electrical activity, and therefore K(ATP) channels regulate insulin secretion. We assume that down-regulating the expression of Kir6.2 subunits of K(ATP) channels may change calcium influx induced by glucose and insulin secretion regulated by K(ATP) channels. In our study, we employ Kir6.2-shRNA plasmid to downregulate Kir6.2 expression in HIT-T15 cells. Then, we research the effect of downregulation of Kir6.2 on K(ATP) current, cytoplasmic free Ca2+ concentration and insulin secretion. All results illustrate that downregulation of Kir6.2 subunits of K(ATP) channels in HIT-T15 cells affects K(ATP) current and insulin secretion, and fails to promote calcium influx. The results demonstrate the function of Kir6.2 subunits in electrophysiology characteristic, insulin secretion and calcium influx, and RNA interference provides a feasible alternative to study the function of Kir6.2 subunits in K(ATP) channels in different kinds of diabetes.
authors.affiliation: Experimental Teaching Center of Life Sciences, Shanghai University School of Life Science, Shanghai University, Shanghai, China. chenfuxue@staff.shu.edu.cn
authors.forename: Fuxue
authors.initials: F
authors.lastname: Chen
authors.forename: Da
authors.initials: D
authors.lastname: Zheng
authors.forename: Yaming
authors.initials: Y
authors.lastname: Xu
authors.forename: Youqun
authors.initials: Y
authors.lastname: Luo
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Kangkang
authors.initials: K
authors.lastname: Yu
authors.forename: Yichao
authors.initials: Y
authors.lastname: Song
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhong
authors.forename: Yonghua
authors.initials: Y
authors.lastname: Ji
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D006224:Cricetinae; D015536:Down-Regulation; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism; D054086:KATP Channels / Q000502:physiology; D024661:Potassium Channels, Inwardly Rectifying / Q000037:antagonists & inhibitors / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D034741:RNA, Small Interfering / Q000235:genetics; D014162:Transfection; D000099161:Kcnj11 Channel
chemical_list: D002118:Calcium; D007328:Insulin; D054086:KATP Channels; D024661:Potassium Channels, Inwardly Rectifying; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D000099161:Kcnj11 Channel