Alteration of adenylate cyclase activity by phosphorylation and dephosphorylation

Abstract

Incubation of S49 cell membranes at 0°C resulted in a loss of adenylate cyclase activity, but addition of ATP and ATP regenerating system prevented the decrease of the activity. A non-phosphorylating analogue of ATP, adenyl-5′-yl imidodiphosphate, was less effective than ATP. Treatment of solubilized adenylate cyclase with calf intestine alkaline phosphatase caused the decrease of the activity. Membranes from cyc − S49 mutant cells, which are devoid of guanine nucleotide-binding protein, yielded the same results as membranes from S49 cells, indicating that the catalytic component is involved in the alteration of the enzyme activity by these treatments. These results suggest that phosphorylation and dephosphorylation of the catalytic component may regulate adenylate cyclase activity.