RAS ONCOGENE-INDUCED TRANSFORMATION OF A RAT SEMINAL-VESICLE EPITHELIAL-CELL LINE PRODUCES A MARKED INCREASE OF ADENYLATE-CYCLASE AND PROTEIN-KINASE-C ACTIVITIES

Cells transformed by Kirsten murine sarcoma virus (Ki-MSV) have basal adenylate cyclase activity (AC) higher than control cells and comparab le level of forskolin-stimulated AC activity. Moreover, a higher prote in kinase C (PKC) activity was found to be present in the transformed cells. The molecular mechanism underlying the increase of AC activity was investigated. Our findings strongly suggest that this biochemical event is due to a marked decrease of the alpha(i) negative control of the enzyme, even though the alpha(i) of transformed cells appears to p ossess fully functional domains interacting with both the effector enz yme and the agonist-activated receptor.