Similar correlation analysis at D8 (in control D8 and decitabine-treated cells), indicated that Mecp2e1 shows a significant negative correlation with average DNA methylation at the promoter R1 (r > -0.7, P <0.05), R2 (r > -0.8, P <0.05) and R3 (r > -0.7, P = 0.06, close to significant) and a significant positive correlation with the average DNA methylation at the intron 1 R6 (r >0.9, P <0.001) (Figure 7A, b). In contrast, Mecp2e2 did not show any significant correlation with any of the promoter regions (R1 to R3), but showed a significant positive correlation with the average methylation at intron 1 R4 (r >0.9, P <0.05) and R6 (r >0.9, P <0.01). This divergence in the correlation patterns (negative and positive depending on the stage of differentiation), might imply a potential dynamic role of DNA methylation in regulating Mecp2 isoforms at different stages of NSC differentiation.
