孔道关键氨基酸残基对电压门控钾离子通道Kv2.1和Kv2.2离子选择性的调控  

Regulation of Ion Selectivity by Key Pore-forming Residues in Voltage-gated Potassium Channels Kv2.1 and Kv2.2

作　　者：刘翠云 胡长龙[1] LIU Cuiyun;HU Changlong(Department of Physiology and Biophysics,School of Life Sciences,Fudan University,Shanghai 200438,China)

机构地区：[1]复旦大学生命科学学院

出　　处：《复旦学报（自然科学版）》2019年第5期596-604,共9页Journal of Fudan University：Natural Science

基　　金：教育部博士点基金(20100071120022)

摘　　要：哺乳动物电压门控钾离子通道在膜电位维持以及介导神经元和肌肉兴奋性方面发挥了关键性的作用,与多种神经和心血管疾病密切相关.本研究主要运用点突变方法和膜片钳技术探究W366,Y376以及W374,Y384之间的氢键对哺乳动物大鼠Kv2.1和Kv2.2通道结构和功能的影响.实验证明破坏该氢键会导致通道丧失钾离子通透能力,而主要通透钠离子.Mammalian voltage-gated potassium(Kv)channels,playing key roles in maintaining membrane potential and mediating neuronal and muscular excitability,and have been implicated in various neuronal and cardiovascular diseases.In this study,by point mutation and Patch clamp technique,we test whether the inter-subunit H-bond formed by W366-Y376 and W374-Y384 play an important role in regulating the function of mammalian Kv2.1 and Kv2.2 channels.We found that the mutation of either of the two residues resulted in losing selectivity for K^+ and allowing influx of Na^+.We also found that Na^+ is the mainly permeable ion in the mutant channels.

关 键 词：电压门控钾离子通道(Kv) 氢键 离子通透性 

分 类 号：Q424[生物学—神经生物学]