R5 (13.08%, P <0.05), and R6 (CpG1, 8.01%, P <0.01; CpG2, 3.8%, P = 0.4) (Figure 6A, d-f), with significant demethylation at the entire intron 1 (10.37%, P <0.05) (Figure 6B, b). These results indicated that decitabine induced significant DNA demethylation at both the Mecp2 promoter and intron 1, at the individual CpG sites and the overall DNA methylation. As mentioned earlier, this detected DNA demethylation was associated with significant upregulation of Mecp2e1 isoform, but not Mecp2e2. Therefore, it is possible that the observed changes in DNA methylation at the studied REs contribute to the upregulation of Mecp2e1.
