Effect of ACTH on the stability of mRNAs encoding bovine adrenocortical P-450scc, P-45011 beta, P-45017 alpha, P-450C21 and adrenodoxin.

ACTH treatment of bovine adrenocortical cells in primary culture causes increased accumulation of mRNAs encoding cytochromes P-450SCC, P-450(11)beta, P-450(17) alpha, P-450C21 and adrenodoxin as well as increased transcriptional activity of their respective genes. In this study we have shown that ACTH does not greatly affect the half-life of mRNAs encoding P-450(11)beta, P-450(17)alpha, P-450C21 and adrenodoxin. However, in the case of P-450SCC mRNA, ACTH causes a five-fold increase in the half-life leading to a significant stabilization of P-450SCC mRNA. Thus it appears that the levels of mRNAs encoding P-450(11)beta, P-450(17)alpha, P-450C21 and adrenodoxin are regulated by ACTH primarily at the transcriptional level, while that for P-450SCC is regulated at both the transcriptional and post-transcriptional levels.