CX26不同结构域错义突变体的表达和定位

The Expressions and Localizations of Nine Missense Mutants of CX26 in HeLa Cells

杨中纯;肖自安;谢鼎华;

1:中南大学湘雅二医院耳鼻咽喉-头颈外科

摘要
目的探讨CX26蛋白质的9个结构域上的不同错义突变体在细胞内的表达及功能改变的异同,初步研究CX26不同错义突变体的致聋机理。方法在CX26的9个结构域中各选择1个致聋的错义突变(p.S19T、p.R32H、p.E47K、p.V84L、p.V95M、p.R143W、p.R165W、p.S199F、p.L214P),应用重叠区扩增基因拼接法和长引物快速法,构建成与增强型绿色荧光蛋白(EGFP)融合表达的载体,野生型CX26-EGFP作对照,脂质体转染HeLa细胞,Westernblot分析蛋白的表达,共聚焦显微镜下观察各突变体在细胞膜上有无间隙连接斑形成。结果 CX26的9个结构域上的各1个错义突变体在HeLa细胞中均有表达,其中p.S19T、p.E47K、p.V84L、p.V95M和p.vR165W突变体能在细胞膜上表达并形成间隙连接斑,p.R32H、p.R143W、p.S199F和p.L214P突变体在细胞浆中表达,在细胞膜无表达,无间隙连接斑形成。结论 CX26的p.S19T、p.E47K、p.V84L、p.V95M和p.R165W突变体在细胞内能被转运到细胞膜并形成间隙连接,而p.R32H、p.R143W、p.S199F和p.L214P突变体失去被转运到细胞膜的功能,不能形成间隙连接。CX26的不同错义突变的致聋机制可能不同,与突变点所在的结构域可能没有相关性。
关键词
连接蛋白26(CX26);突变体;表达;间隙连接
基金项目(Foundation):
国家自然科学基金(30000094,30572021);; 中南大学博士后基金(56890)资助
作者
杨中纯;肖自安;谢鼎华;
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