Simultaneous single-molecule epigenetic imaging of DNA methylation and hydroxymethylation
Song C-X., Diao J., Brunger AT., Quake SR.
Significance DNA epigenetic modifications in the forms of 5-methylcytosine (5mC) and 5-hydroxylmethylcytosine (5hmC) play crucial regulatory functions in the mammalian genome. Here we developed an ultrasensitive single-molecule epigenetic imaging technology for detecting and quantifying 5hmC and 5mC. By conducting single-molecule fluorescence resonance energy transfer experiments, we discovered high levels of adjacent and opposing methylated and hydroxymethylated CpG sites in the mouse genome, a previously unappreciated structure which may play an important role in gene regulation.