Protection of CpG islands from DNA methylation is DNA-encoded and evolutionarily conserved.

ABSTRACT: DNA methylation is a repressive epigenetic modification that covers vertebrate genomes. Regions known as CpG islands (CGIs), which are refractory to DNA methylation, are often associated with gene promoters and play central roles in gene regulation. Yet how CGIs in their normal genomic context evade the DNA methylation machinery and whether these mechanisms are evolutionarily conserved remains enigmatic. To address these fundamental questions we exploited a transchromosomic animal model and genomic approaches to understand how the hypomethylated state is formed in vivo and to discover whether mechanisms governing CGI formation are evolutionarily conserved. Strikingly, insertion of a human chromosome into mouse revealed that promoter-associated CGIs are refractory to DNA methylation regardl

SUBMITTER: Long HK 

PROVIDER: S-EPMC5001583 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature