(A) Histogram depicts normalized values of Mos concentration at GVBD time in control oocytes treated with DMSO vehicle (0%,1%) and in U0126-treated oocytes (50 μM). Mos levels are, respectively, 1±0.22 and 0.83±0.27. (B) Cell by cell analysis by western blot for contents in Mos, MAPK, cyclin B2, phospho-tyrosine 15 Cdc2, and actin. Oocytes were taken at GVBD time for biochemical analysis.