The effects of gossypol on nuclear protein in rat testes. II. The synthesis of histones and testis-specific proteins after gossypol treatment.

This communication is to report the effects of gossypol on the synthesis of chromosomal basic proteins in the spermiogenic cells. A double-labelling experiment has been performed. The control rats received 14C-arginine, whereas the gossypol-treated rats received a 3H-arginine injection. An equal volume of the tissues (from control and gossypol-treated) were combined, and the total nuclear basic proteins (TNBP) from round spermatids (RS) and elongating spermatids (ES) were extracted for electrophoretic separation. By studying the ratio of 3H/14C, it was indicated that the synthesis of H1, H3, H2B plus H2A and TP1 in the RS was reduced by gossypol. The amount of inhibition of these proteins were 48%, 19%, 27%, and 11%, respectively. In the ES, the synthesis of H1, H3, H2B plus H2A, H4 plus TP2, TP3, and TP1 was reduced by gossypol, the reduction was 33%, 22%, 26%, 14%, 33%, and 8%, respectively. The synthesis of S1 protein was not inhibited by gossypol in both RS and ES.