Effect of androgen on the transcription of rat prostatic binding protein genes.

The mechanisms whereby androgens modulate mRNA levels for the C1, C2 and C3 prostatic binding protein genes in the rat ventral prostate have been investigated. Transcription rates for the 3 genes were lowered 2-3-fold upon castration but found to increase again upon re-administration of testosterone. Although this demonstrated a direct effect of androgens at the transcriptional level for these genes, the rates of mRNA synthesis were insufficient to account for previously observed steady-state measurements. This was confirmed by analysis of the nuclear steady-state levels for each mRNA following hormonal manipulation of the rats in vivo. It is concluded that besides direct transcriptional regulation, androgens must also exert a major effect of the half-life of these mRNAs in the rat ventral prostate.