Figure 1.

DNMT3L deficiency in mESCs results in hypomethylation at specific heterochromatin regions. (A) Mouse breeding strategies to generate mESC lines with different Dnmt3l genotypes. (B and C) Western blot analysis of the mESC lines (2 independent clones per genotype) for expression of DNMT3L (B) and the pluripotency factors OCT4 and SOX2 (C), with β-ACTIN serving as a loading control. (D and E) Southern blot analysis of the mESC lines (2-3 independent clones per genotype) for DNA methylation at the major satellite repeats (D) and the minor satellite repeats (E) after digestion of genomic DNA with methylation-sensitive restriction enzymes (MaeII for major satellite repeats and HpaII for minor satellite repeats). DKO, Dnmt3a/3b double KO mESC line.