INHIBITORS OF RNA AND PROTEIN-SYNTHESIS STABILIZE MESSENGER-RNA FOR THE RII-BETA-SUBUNIT OF PROTEIN KINASE-A IN DIFFERENT CELLULAR COMPARTMENTS

Messenger RNA for RIIβ is transiently induced (>50-fold) by cAMP analogs in primary cultures of rat Sertoli cells. The induction is dependent on protein synthesis. We have previously shown that mRNA for RIIβ is stabilized by cAMP, as well as inhibitors of transcription and translation. This indicated that rapid degradation of RIIβ mRNA involved a protein with a rapid turnover and its corresponding mRNA. The two RNA synthesis inhibitors used in the present study stabilized both nuclear and cytoplasmic RIIβ mRNA, whereas inhibition of protein synthesis stabilized RIIβ mRNA in the cytoplasm only. These results indicate that only cytoplasmic degradation of RIIβ mRNA is dependent on a protein with high turnover. In contrast, nuclear degradation appears to be dependent on an RNA with a short half-life, not involving protein synthesis. © 1992.