Fig. 7. Phosphorylated isoforms of both GST-V and endogenous HDACm can be detected in GVs. (A) Immunoblots of GST-V, T445A and 3m from GVs and cytoplasms isolated at 4 hours post-injection into the cytoplasm. Bars on the left indicate the positions of three possible isoforms. (B) Dephosphorylation of nuclear HDACm in vivo during oocyte maturation. Stage VI oocytes were treated with 0.5 µM progesterone to induce maturation and GVs and cytoplasms were isolated at 0, 2 and 4 hours. Samples taken at 4 hours post-hormone were also treated with 2 units/µl of alkaline phosphatase. Immunoblot using antibody directed against the C-terminal peptide of HDACm. GST-V is shown as a non-phosphorylated control for antibody detection. Bars on the left indicate the positions of four possible isoforms, the fastest migrating of which corresponds to non-phosphorylated HDACm at 57 kDa.