Fig. 3. Electrophoretic mobility of EDEN-BP changes during oocyte maturation and activation. (A) Stage VI oocytes were incubated in Merriam buffer and maturated in vitro by addition of 1 µM progesterone. Samples of 20 oocytes were collected at 0, 1, 2, 4 and 5-9 hours after progesterone addition. The GVBD status was estimated as the percentage of oocytes showing the maturation spot (% GVBD). The samples were extracted, analysed by electrophoresis and immunoblotted with anti EDEN-BP antibody. (B) Unfertilized eggs were treated (+) or not (-) with calcium ionophore. Samples of ten parthenogenetic embryos were collected every 15 minutes during the first hour postactivation, and then every 30 minutes. Extracts were analysed as described above. The positions of different electrophoretic forms of EDEN-BP are indicated on the right of the blot.