Kaiso mainly locates in the nucleus in vivo and binds to methylated,but not hydroxymethylated DNA  

作　　者：Sisi Qin Baozhen Zhang Wei Tian Liankun Gu Zheming Lu Dajun Deng 

机构地区：[1]Beijing Key Laboratory of Carcinogenesis and Translational Research,Division of Cancer Etiology,Peking University Cancer Hospital & Institute

出　　处：《Chinese Journal of Cancer Research》2015年第2期148-155,共8页中国癌症研究（英文版）

基　　金：supported by National Basic Research Program of China(Grant No.2011CB504201)

摘　　要：Objective： Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization in vivo and exact binding DNA sequences in cells. Methods： Compartmentalization of exogenous Kaiso in cells was tracked with enhanced green fluorescence protein （EGFP） tag. The endogenous Kaiso expression in gastric carcinoma tissue was examined with immunohistochemical staining. Kaiso-DNA binding was tested using electrophoretic mobility shift assay （EMSA） and chromatin immunoprecipitation assay （CHIP）. Results： Kaiso mainly localized in the nucleus of cancer and stromal cells in vivo, but remained in the cytoplasm of cultured cells. Most importantly, nuclear Kaiso can bind with the methylated-CGCG- containing sequence in the CDKN2A promoter, but not with the hydroxymethylated-CGCG sequence in HCT116 cells. Conclusions： Kaiso locates mainly in the nucleus in vivo where it binds with the methylated-CGCG sequences, but does not bind with the hydroxymethylated-CGCG sequences.Objective： Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization in vivo and exact binding DNA sequences in cells. Methods： Compartmentalization of exogenous Kaiso in cells was tracked with enhanced green fluorescence protein （EGFP） tag. The endogenous Kaiso expression in gastric carcinoma tissue was examined with immunohistochemical staining. Kaiso-DNA binding was tested using electrophoretic mobility shift assay （EMSA） and chromatin immunoprecipitation assay （CHIP）. Results： Kaiso mainly localized in the nucleus of cancer and stromal cells in vivo, but remained in the cytoplasm of cultured cells. Most importantly, nuclear Kaiso can bind with the methylated-CGCG- containing sequence in the CDKN2A promoter, but not with the hydroxymethylated-CGCG sequence in HCT116 cells. Conclusions： Kaiso locates mainly in the nucleus in vivo where it binds with the methylated-CGCG sequences, but does not bind with the hydroxymethylated-CGCG sequences.

关 键 词：Kaiso COMPARTMENTALIZATION DNA binding METHYLATION HYDROXYMETHYLATION CDKN2A 

分 类 号：R730.2[医药卫生—肿瘤]