title: Participation of adenosine 5'-triphosphate in the activation of membrane-bound guanylate cyclase by the atrial natriuretic factor.
abstract: The addition of ANF to Percoll-purified liver plasma membranes produced a slight activation of guanylate cyclase; the ANF-stimulated cyclase activity was further increased upon the addition of ATP to the enzyme assay mixture. The effect of ATP to potentiate the cyclase activation was concentration-dependent, required Mg2+ as a divalent cation, and was seen with membranes from various tissues and cells. ATP increased the maximal velocity of the cyclase without a change in the affinity for GTP or ANF. Phosphorylation by ATP might not be involved since ANF-stimulated guanylate cyclase was enhanced by non-phosphorylating ATP analogues as well. Thus, an allosteric ATP binding site is suggested to participate in ANF-induced regulation of membrane-bound guanylate cyclase.
mesh_terms: D000227:Adenine Nucleotides / Q000494:pharmacology; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002462:Cell Membrane / Q000201:enzymology; D004789:Enzyme Activation; D006162:Guanylate Cyclase / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D009928:Organ Specificity; D051381:Rats; D012265:Ribonucleotides / Q000494:pharmacology
chemical_list: D000227:Adenine Nucleotides; D012265:Ribonucleotides; D009320:Atrial Natriuretic Factor; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D006162:Guanylate Cyclase