Fig. 2: Hemi-methylated CpG sites are shared targets of the two types of demethylation.

a, b CpG sites and genes were sorted according to the enrichment of hemi-methylation (AMDs between the positive and negative strands) and grouped into 14 and 20 groups, respectively. The demethylation of different groups was plotted against their enrichment of hemi-methylation (AMDs). c Schematic illustration of the in vitro model used to determine TET1 activity. d, e Dose-dependent (d) and time-dependent (e) curves of TET1-containing nuclear extraction to demethylate hemi- and full-methylated CpG sites. f Mutation of TET1 failed to induce demethylation in the current in vitro model. g The abilities of purified TET1 protein to demethylate hemi-methylated and full-methylated CpG sites. h Schematic illustration of the different demethylation induced by sh-Dnmt1 and Tet1. i The abilities of sh-Dnmt1 and Tet1 to influence the amounts of hemi-methylated CpG sites