Patterns of Protein Synthesis at the Onset of Oogenesis in the Mouse

Two-dimensional electrophoresis has been used to examine the pattern of proteins synthesized in germ cells at the beginning of oogenesis in the mouse. Three stage-specific changes in proteins were detected during the three observational periods studied (12,14, and 17 days of gestation). One protein is present in 12 day female germ cells and nongerminal gonadal preparations, but disappears by day 14. Two of the proteins appear for the first time in fourteen day female germ cell preparations, and are not detectable in nongerminal gonadal tissue. No stage-specific changes in proteins were observed in preparations of male germ cells of the same age. A preliminary DNA-binding protein analysis suggests that none of the stage-specific proteins mentioned above are DNA-binding proteins.