Fig. 7. Relationship between H3/K9 and DNA cytosine methylation in the male pronucleus following transplantation into GV-stage or MII-stage oocytes. Reconstructed oocytes were produced by transferring male pronuclei into enucleated GV-stage oocytes, followed by a 3-hour culture to retrieve meiosis (NT-GVB) or to inhibit meiotic resumption in the presence of IBMX (NT-GV). Alternatively, the male pronuclei were transferred into enucleated MII-stage oocytes (NT-MII), followed by culture for 3 hours in the presence of nocodazole to prevent spontaneous activation. The antibodies directed against H3/K9 methylation (MeH3K9) and DNA cytosine methylation (5-MeC) were detected using the cy3-conjugated secondary antibody (red) and the FITC-conjugated secondary antibody (green), respectively. The reconstruction experiments for the NT-GVB, NT-GV and NT-MII oocytes were conducted three times. In total, 18 NT-GVB, 20 NT-GV and 18 NT-MII oocytes were reconstructed successfully and examined for histone methylation. Similar patterns were observed for each type of reconstructed oocytes; representative examples are shown.