磺脲类受体在小窝蛋白与心肌钾离子通道偶联中的作用  

Role of sulfonylurea receptor in coupling of caveolin to myocardial potassium ion channel

作　　者：潘肃[1] 杨宇丹[1] 吕晓明[1] 杨小玉[1] 遇红梅[1] 

机构地区：[1]吉林大学中日联谊医院,吉林长春130033

出　　处：《中国生物制品学杂志》2015年第9期918-922,共5页Chinese Journal of Biologicals

基　　金：国家自然科学基金(81250016);吉林省科技发展计划青年科研基金项目(20130522039JH;20130522032JH)

摘　　要：目的分析磺脲类受体在小窝蛋白(caveolin,Cav)与心肌钾离子通道偶联中的作用,探讨心肌钾离子通道与Cav-3偶联的分子机制。方法将野生型或突变型KATP通道与Cav-3瞬时转染入COS-7细胞中,通过免疫共沉淀和荧光染色法观察KATP通道与Cav-3共定位及偶联情况;同时应用Cav-3脚手架区竞争性抑制肽封闭Cav-3脚手架区,重复上述试验。结果 Cav-3脚手架区竞争性抑制肽能够结合Cav脚手架区,从而显著封闭Cav与野生型KATP通道免疫沉淀结合量,但不影响与突变型KATP通道偶联量;荧光染色显示,Cav与野生型KATP通道荧光重叠显著高于突变型KATP通道,二者共定位于细胞内同一位置。结论野生型KATP通道中SUR2A对于Cav-3与心肌KATP通道偶联至关重要,二者偶联是通过Cav-3脚手架区实现的。Objective To analyze the role of sulfonylurea receptor in coupling of caveolin（Cav）to myocardial potassium ion channel as well as the relevant molecular mechanism. Methods COS-7 cells were transiently transfected with wild type or mutant KATPchannel and Cav-3, in which he co-localization and coupling of KATPchannel and Cav-3 were observed by co-immunoprecipitation and fluorescent staining. The test was repeated after Cav-3 scaffold region was blocked with its competitive inhibiting peptide. Results The competitive inhibiting peptide of Cav-3 scaffold region bound to the region thus blocked the binding of Cav to wild type KATPchannel while showed no influence on the coupling to mutant KATP channel. Fluorescent staining showed that the overlapping level of Cav with wild type KATPchannel was significantly higher than that with mutant KATPchannel. Cav and wild type KATPchannel were localized in the same position in cells.Conclusion The SUR2 A in wild type KATPchannel was important to the coupling of Cav-3 to myocardial KATPchannel.The coupling was achieved through the Cav-3 scaffold region.

关 键 词：磺脲类受体 钾离子通道 小窝蛋白 

分 类 号：Q257[生物学—细胞生物学]