title: N-CoR mediates DNA methylation-dependent repression through a methyl CpG binding protein Kaiso.
abstract: The identification and characterization of molecular mechanisms utilized by cells to mediate transcriptional repression at methylated loci are fundamental to understanding the biological consequences of DNA methylation. Here we demonstrate that Kaiso, a methyl CpG binding protein belonging to the BTB/POZ family of transcription factors, is a component of the human N-CoR complex. In vitro, the Kaiso/N-CoR complex binds specific CpG-rich sequences in a methylation-dependent manner. In vivo, Kaiso targets the N-CoR complex to the MTA2 gene promoter in a methylation-dependent manner. Importantly, we demonstrate that Kaiso is required for transcriptional repression of the methylated MTA2 locus. Furthermore, this repression also requires a functional N-CoR deacetylase complex, which brings about histone hypoacetylation and methylation of H3 lysine 9 to the MTA2 locus. Thus, our data demonstrate a critical role for a methyl CpG binding protein in mediating DNA methylation-dependent repression and reveal the mechanism by which it represses transcription.
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
authors.forename: Ho-Geun
authors.initials: HG
authors.lastname: Yoon
authors.forename: Doug W
authors.initials: DW
authors.lastname: Chan
authors.forename: Albert B
authors.initials: AB
authors.lastname: Reynolds
authors.forename: Jun
authors.initials: J
authors.lastname: Qin
authors.forename: Jiemin
authors.initials: J
authors.lastname: Wong
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D018899:CpG Islands / Q000235:genetics*; D019175:DNA Methylation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015257:DNA-Cytosine Methylases / Q000235:genetics / Q000378:metabolism; D005057:Eukaryotic Cells / Q000378:metabolism; D005809:Genes, Regulator / Q000235:genetics*; D006367:HeLa Cells; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008239:Lysine / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D056971:Nuclear Receptor Co-Repressor 1; D011401:Promoter Regions, Genetic / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D006657:Histones; C539127:NCOR1 protein, human; D009687:Nuclear Proteins; D056971:Nuclear Receptor Co-Repressor 1; D012097:Repressor Proteins; D014157:Transcription Factors; C492254:ZBTB33 protein, human; C081573:DNA modification methylase SssI; D015257:DNA-Cytosine Methylases; C120917:MTA2 protein, human; D006655:Histone Deacetylases; D008239:Lysine