Figure 1.

Germinal vesicle breakdown (GVBD) in severe DNA DSBs oocytes induced by zeocin. (A) Zeocin induced severe DNA DSBs at a high concentration. Fully grown GV oocytes were treated with 200 μg/ml zeocin for 1 h in M2 medium supplemented with 2.5 μM milrinone, while oocytes blocked for 1 h by milrinone were used as control. Oocytes were immunostained with anti-Pi-H2AX antibody immediately after 1 h treatment with or without zeocin (A), or after additional 5 h of IVM in M2 medium (B). (C) The GVBD rates were analyzed in the 2 groups from 2 h of IVM to 5 h of IVM. Asterisks indicate significant differences compared to the control group (P < 0.05).