Restriction enzyme (RE) digestion was performed for the bisulphite PCR product of all ES samples, and “Cut” (Lane 1) but not “Uncut” (Lane 2) control wild-type mouse tail DNA sample. U and M, unmethylated (U) and methylated (M) product after RE digestion, respectively. Lanes 3–10, eight Zfp57+/− (M+Z+) ES clones derived from the blastocysts generated from the cross between Zfp57+/− heterozygous female mice and Zfp57−/− homozygous male mice. Lanes 11–13, three Zfp57−/− (M+Z−) ES clones derived from the blastocysts generated from the cross between Zfp57+/− heterozygous female mice and Zfp57−/− homozygous male mice. Lanes 14–18, five Zfp57−/− (M−Z−) ES clones derived from the cross between Zfp57−/− homozygous female mice and Zfp57−/− homozygous male mice.
A, COBRA analysis was carried out at the IG-DMR of the Dlk1-Dio3 imprinted region, H19 DMR of the Igf2-H19 imprinted region and Rasgrf1 DMR.
B, COBRA analysis of the IAP repeats.