Cardiac sarcolemmal substrate of the cGMP-dependent protein kinase.
Cardiac sarcolemmae from guinea pig ventricles were purified and incubated with cGMP-dependent protein kinase. In the presence of the purified kinase plus 10(-5) M cGMP or 8-Br-cGMP, a protein of approximately 50 kD, (Kilodalton) was phosphorylated. This membrane-associated cGMP-dependent protein kinase substrate is similar in MW to the regulatory subunit of the cAMP-dependent protein kinase, which is known to be a substrate for the cGMP-dependent protein kinase. Thus, this substrate, the identity of which remains to be proven, may be a possible mediator of cGMP-mediated control of cardiac function.
Cuppoletti
J
J
Department of Physiology and Biophysics, University of Cincinnati, College of Medicine, Ohio 45267-0576.
Thakkar
J
J
Sperelakis
N
N
Wahler
G
G
D000818:Animals; D006152:Cyclic GMP / Q000032:analysis / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006168:Guinea Pigs; D008565:Membrane Proteins / Q000378:metabolism*; D009206:Myocardium / Q000648:ultrastructure*; D010766:Phosphorylation; D011494:Protein Kinases / Q000032:analysis / Q000378:metabolism*; D012508:Sarcolemma / Q000032:analysis / Q000378:metabolism*; D013379:Substrate Specificity
D008565:Membrane Proteins; D011494:Protein Kinases; D006152:Cyclic GMP