A) Oocytes were fixed for chromosome spreads 8 hours after GVBD, and stained for PP2A-c (red), Sgo2 (green), CREST (blue) and DNA (Hoechst, shown in grey). Spreads were classified into metaphase I and anaphase I, depending on whether chromosome segregation had taken place, or not. Arrowhead indicates fused sister kinetochores, arrows indicate separated sister kinetochores. 