Fig. 3: Role of DNMTs in methylation imprints and maintenance methylation.
a Genome browser tracks of WGBS methylation profiles at the H19 and Impact imprinted loci in early embryos and Dnmt mutant embryos. One WGBS replicate is shown. The positions of the imprinted germline DMRs (gDMRs) are depicted by purple rectangles. b Boxplots of the CG methylation levels of n = 20 imprinted germline DMRs measured by WGBS in WT, Dnmt1−/− and DKO embryos. In the boxplots the line indicates the median, the box limits indicate the upper and lower quartiles and the whiskers extend to 1.5 IQR from the quartiles. c Fold change of expression of imprinted genes in Dnmt1−/− (red bars) and DKO (green bars) embryos (n = 3 embryos for Dnmt1−/−; n = 6 embryos for DKO). **p < 0.01; ***p < 0.001 (adjusted p value calculated by DESeq2 using a Wald test corrected for multiple testing). d Experimental outline for investigating the maintenance function of DNMT3A/B in MEFs. Dnmt3a2lox/2lox Dnmt3b2lox/2lox immortalized MEFs expressing Cre-ERT2 were treated with Tamoxifen to generate conditional double knockout (cDKO) cells, and methylation was quantified by RRBS after long-term passaging. e Evaluation by PCR genotyping of the Cre-mediated recombination of the Dnmt3a and Dnmt3b-2lox alleles in cDKO fibroblasts. The number of days of Tamoxifen treatment is indicated above the gels. f CG methylation levels quantified by RRBS in cDKO fibroblasts. The graph shows the methylation levels in CpG islands (CGI), non-CGI regions, and imprinted gDMRs in cells treated with Tamoxifen (Tam) or not treated with Tamoxifen (no Tam) after 23 and 69 days of culture (mean ± SEM, n = 3 biological replicates), revealing no global hypomethylation in cDKO MEFs. Source data are provided as a Source data file.
