Autophosphorylation of cGMP-dependent protein kinase is stimulated only by occupancy of one the two cGMP binding sites

• Published in: FEBS letters Vol. 164; no. 2; pp. 350 - 354
• Main Authors: Hofmann, Franz, Gensheimer, Hans-Peter, Gobel, Claus
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 12.12.1983; Elsevier
• Subjects: 8-Benzyl-amino-cAMP; Adenosine Triphosphate - metabolism; Analytical, structural and metabolic biochemistry; Autophosphorylation; Binding Sites; Biological and medical sciences; cGMP-dependent protein kinase; Cyclic AMP - analogs & derivatives; Cyclic AMP - pharmacology; cyclic GMP; Cyclic GMP - metabolism; Dibutyryl Cyclic GMP - analogs & derivatives; Dibutyryl Cyclic GMP - pharmacology; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; Kinetics; N 2-Monobutyryl-c-GMP; N2-Monobutyryl-c-GMP; Phosphorylation; protein kinase; Protein Kinases - metabolism; Transferases; cGMP-dependent protein kinase; Autophosphorylation; 8-Benzyl-amino-cAMP; N 2-Monobutyryl-c-GMP; Site specificity; Phosphorylation; Enzyme; Protein kinase; 3',5'-GMP; Binding site; Cyclic-GMP dependent protein kinase
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(83)80315-9

cGMP-Dependent protein kinase contains, per subunit, 2 binding for cGMP. The apparent K D values for site 1 and 2 were 12 and 55 nM. The analogues 8-benzyl-amino-cAMP and N 2-monobutyryl-cGMP bind preferentially to site 1 and 2, respectively. Both analogues stimulate autophosphorylation of the enzyme at concentrations at which only half of the phosphotrasferase activity of the enzyme is expressed. Complete expression of the phosphotransferase activity requires a high concentration of each analogue and is accompanied by inhibition of the autophosphorylation reactions. It is concluded that occupancy of site 1 or 2 stimulates autophosphorylation while occupancy of both sites prevents autophosphorylation.