The catalytic unit of ram sperm adenylate cyclase can be activated through the guanine nucleotide regulatory component and prostaglandin receptors of human erythrocyte.

Ram sperm adenylate cyclase is insensitive to fluoride, guanine nucleotides, cholera toxin, and hormones, and appears devoid of the guanine nucleotide regulatory component. In this paper, we demonstrate that human erythrocyte membranes are capable of restoring guanine nucleotide regulation and fluoride sensitivity to ram sperm adenylate cyclase. The reconstitution process in the presence of guanyl-5'-yl imidodiphosphate or NaF is time-dependent, directly proportional to the quantity of erythrocyte protein added to the reconstitution system, and is only observed when Mg-ATP is used as substrate. Furthermore, the guanyl-5'-yl imidodiphosphate-reconstituted activity can be activated by prostaglandin E1 or prostaglandin E2 through the binding sites normally present in human erythrocyte membranes. It therefore appears that reconstitution of the adenylate cyclase system can be readily performed in normal membranes which are deficient in regulatory component, and not only using defective cultured cell lines.