Fig. 4. Demethylation of histone H3-K9 in somatic nuclei after being injected into intact mouse GV oocytes and enucleated GV oocytes. (A,B) Oocytes were examined after culture for 0, 1, 3 and 7 hours. Methylation of H3-K9 is shown in green and microtubules are stained for β-tubulin in red. (B) After nuclear transfer in enucleated GV oocytes, somatic chromosome formed structures similar to fully grown GV chromosome after 1 hour (m) and similar to late GV chromosome after 2 hours (n). OC, oocyte chromosome; SC, somatic chromosome. Arrow indicates an intact cumulus cell before injection. Scale bars: 20 µm.