Figure 3.

Global levels of 5hmC and 5mC in DMOG-treated blastocysts. (a) Timeline of DMOG treatment to inhibit TET activities in blastocysts. To block TET activities at blastocyst stage, embryos were incubated with 1 mM DMOG from morula stage (d 4) to blastocyst stage (d 7); then, blastocysts were collected for further analysis. (b) Global 5hmC level of blastocysts was dramatically decreased by DMOG treatment. (c) Difference of global 5mC level between DMOG-treated and control blastocysts was not detected by immunocytochemistry. Numbers in parentheses indicate the number of embryos displaying a positive signal for 5hmC or 5mC out of the total number of embryos examined. (d) Bisulphite sequencing analysis of DNA methylation pattern in repetitive elements. Methylation level of PRE-1 was increased by DMOG treatment whereas centromeric satellites were hypomethylated in both DMOG-treated (n = 15) and control blastocysts (n = 16). Scale bar indicates 100 µm. Methylated and unmethylated CpG dinucleotides are indicated by filled circle and open circle, respectively