Quantitation of mRNAs during Mouse Spermatogenesis: Protamine-Like Histone and Phosphoglycerate Kinase-2 mRNAs Increase after Meiosis

Total RNA, prepared from immature or mature mouse testes or from spermatogenic cells separated on the basis of sedimentation velocity, was translated in vitro. Mouse protamine-like histone could be identified as an in vitro translational product when [3H]arginine was used as the label. The mRNA for protamine-like histone was detected only after meiosis; the appearance of a peak of radioactivity comigrating with protamine-like histone occurred only when RNA from mature testes or late spermatid cell fractions was translated. Phosphoglycerate kinase-2 (ATP:3-phospho-D-glycerate 1-phosphotransferase, EC 2.7.2.3) was identified as an in vitro translational product by affinity chromatography followed by two-dimensional gel electrophoresis or by specific immunoprecipitation when [35S]methionine was the label. The mRNA for phosphoglycerate kinase-2 was detected only in mature testes or late spermatid cell fractions. These translational assays for protamine-like histone and phosphoglycerate kinase-2 mRNAs suggest that these messages are transcribed after meiosis.