Methyl binding domains MBDs

Table 5.6 Selected human methyl binding domains (MBDs).

Although chemically modifying DNA have distinctive implications for chromatin transitions and fiber structure in the presence of HI [250], in vivo these effects appear to work in concert with chromosomal proteins. 5 -Methylcytosines are specifically bound by members of the MBD (methyl-CpG-binding-domain) family, such as MeCP2 (Methyl-Cytosine binding Protein 2) and MBDl. These proteins have been shown to interact with HDACs and provide a casual link between DNA methylation, histone deacetylation and transcriptional repression [251-253]. 

The solution structure of the methyl-CpG binding domain of human MBDl complexed with a methylated oligonucleotide has been recently presented [164], The structure indicates how MBD may access nucleosomal DNA without encountering steric hindrance from the histone octamer. 

MBD3 Contains MBD domain and a C-terminal stretch of 12 glutamic acid residues mammalian protein does not bind methylated DNA in vivo or in vitro A component of the Mi2/NuRD and SMRT/HDAC5-7 deacetylase complexes Expressed in somatic tissues and in ES cells... 

MBD4 Contains MBD domain and a repair domain (T-G mismatch glycosylase) Thymine glycosylase that binds to the product of deamination at methylated CpG sites Co-localizes with heavily methylated satellite DNA in mouse cells expressed in somatic tissues and in ES cells... 

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