Changes in chromatin basic proteins during male gametogenesis of grass carp

1. The composition of basic of chromatin protein fractions has been studied in the course of male spermatogenesis of grass carp (Ctenopharyngodon idella). 2. Electrophoretic mobility of H1, H2B and H2A histones of grass carp is shown to differ from that of corresponding fraction of calf thymus histones. 3. Comparison of chromatin protein fractions from liver, mature and immature testis and sperm of grass carp has revealed subtle tissue specificity of H2B and H2A histones. 4. Maturation of spermatozoa in grass carp is accompanied by a marked accumulation of the TH1 subfraction (TH1-1), disappearance of some acid-soluble non-histone proteins and of a protein similar to the mammalian A24 protein.