Figure 3.

YY1 KD effects during oogenesis. About 400 eggs at MII phase were isolated from each of the following two types of female mice: the KD mice (pScio-YY1, Zp3-Cre) and the control (Con) littermates (+, Zp3-Cre). Genomic DNA from these two types of mice was first treated by bisulfite conversion, followed by restriction enzyme digestion (A) and sequencing (B). The PCR product from the H19-ICR was digested by ClaI, while the remaining products from the DMRs of Nespas, Peg3 and Xist were digested by TaqI. The results derived from sequencing of individual PCR products were summarized in the following manner. Each circle represents one CpG site: closed and open ones indicate methylated and unmethylated states, respectively, of the analyzed CpG sites. Each row represents one clone derived from the original PCR product. The methylation levels (%) of each DMR were calculated through dividing the number of methylated CpGs by the total number of surveyed CpG sites. We monitored and compared the purity, number and morphology of the isolated egg samples, and a representative image of the isolated egg is also shown (C).