CpG island clusters and pro-epigenetic selection for CpGs in protein-coding exons of HOX and other transcription factors.

ABSTRACT: CpG dinucleotides contribute to epigenetic mechanisms by being the only site for DNA methylation in mammalian somatic cells. They are also mutation hotspots and approximately 5-fold depleted genome-wide. We report here a study focused on CpG sites in the coding regions of Hox and other transcription factor genes, comparing methylated genomes of Homo sapiens, Mus musculus, and Danio rerio with nonmethylated genomes of Drosophila melanogaster and Caenorhabditis elegans. We analyzed 4-fold degenerate, synonymous codons with the potential for CpG. That is, we studied "silent" changes that do not affect protein products but could damage epigenetic marking. We find that DNA-binding transcription factors and other developmentally relevant genes show, only in methylated genomes, a bimodal distribu

SUBMITTER: Branciamore S 

PROVIDER: S-EPMC2932574 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature