Figure 4.

Expression of D2 inhibits oocyte maturation. (A) Groups of 25–30 oocytes were injected with water or mRNAs encoding the indicated proteins and after overnight incubation were treated with progesterone and scored for GVBD. D2 was found to inhibit or delay progesterone-induced maturation in 27 of 34 experiments. (B) Lysates were prepared from the same oocytes as in A after overnight incubation and analyzed by immunoblotting using anti-myc antibodies. (C) Groups of 25–30 oocytes were injected with water or D2 mRNA, incubated overnight, and then either injected with Mos mRNA or incubated with progesterone. GVBD was scored 8 h later.