Figure 5
From: The de novo methylation activity of Dnmt3a is distinctly different than that of Dnmt1
Model for one of the de novo methylation processes carried out by Dnmt3a and Dnmt1. Dnmt3a initiates methylation on one DNA strand at its preferred CpG sites (filled circles). After DNA replication, Dnmt1 methylates the other strand (open circles) at these hemimethylated sites. The hemimethylated DNA may also stimulate Dnmt1 for further methylation at previous unmethylated CpG sites (open circles indicated with ?).