羧基末端结合蛋白CtBP2与泛素结合酶UBE2Ⅰ的相互作用

目的筛选并确定人羧基末端结合蛋白CtBP2的相互作用蛋白。方法用酵母双杂交技术,以人CtBP2为诱饵蛋白筛选人肝cDNA文库,获得与之相互作用的候选蛋白,采用酵母共转化和细胞免疫共沉淀实验确认相互作用的特异性,最后利用荧光蛋白融合表达技术和荧光显微镜观察确认CtBP2与其相互作用蛋白的亚细胞共定位情况。结果酵母双杂交筛选获得了41个与Bd-CtBP2相互作用的阳性克隆,编码10个不同的蛋白,其中有4个克隆编码泛素结合酶UBE2Ⅰ的不同片段。从人肝cDNA文库中扩增获得UBE2Ⅰ的全长编码序列,酵母共转化和细胞免疫共沉淀实验证实CtBP2与UBE2Ⅰ能够特异性结合。亚细胞定位研究表明GFP-CtBP2弥散分布于细胞核,DsRed-UBE2Ⅰ不均匀分布于细胞核,有部分点状聚集。两者共转染时能够呈点状共定位于细胞核。结论人CtBP2能够在细胞核内与UBE2Ⅰ特异性相互作用,是UBE2Ⅰ的靶蛋白。

Interaction between C-terminal binding protein 2 and ubiquitin-conjugating enzyme E2I

Objective To screen and identify the proteins that can interact with human C-terminal binding protein 2(CtBP2).Methods Yeast two-hybrid screening technique,with CtBP2 as bait protein,was used to screen out the genes of the candidate CtBP2-interacting proteins from human liver cDNA library.Then,yeast co-transformation assay and co-immunoprecipitation assay were performed to confirm the specificity of interaction.Fluorescent fusion proteins and a fluorescence microscope were used for subcellular co-localizati...