Biological activity in the repopulating rat spermatocyte after the withdrawal of gossypol treatment. IV. The activity for the modification of core histones.
Mature male rats were treated with gossypol for 8 weeks. Afterwards, treatment was halted to allow the arrested spermatogonia to revive. Fifteen days after the withdrawal of the drug treatment, the repopulating pachytene spermatocyte (RPS) had a lower level of core histone H3 and H4 acetylation (40 and 55% reduction, respectively) than that of the control pachytene spermatocyte (CPS). The reduction in core histone acetylation was found in histone H3 and H4 but not in H2A and H2B. Forty-five days after the withdrawal of the drug treatment, the inhibitory effect on core histone acetylation was recovered. Both dot-blot and standard liquid assays were used to detect the nuclear histone acetylase activity in RPS and CPS. Fifteen days after the withdrawal of gossypol treatment, the acetylase type A activity in RPS was reduced by 42% when compared to CPS. It has been concluded that after gossypol treatment, the activity for nucleosomal core histones acetylation was selectively inhibited. This effect is related to an inhibitory effect on the histone acetylase activity.
Teng
C S
CS
Department of Anatomy, Physiological Science and Radiology, North Carolina State University, Raleigh.
D000107:Acetylation; D000115:Acetylesterase / Q000378:metabolism; D000818:Animals; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D015870:Gene Expression; D006072:Gossypol / Q000494:pharmacology*; D006657:Histones / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013090:Spermatocytes / Q000187:drug effects*
D006657:Histones; D000115:Acetylesterase; D006072:Gossypol