Related Experiment Videos
Cardiac sarcolemmal substrate of the cGMP-dependent protein kinase
J Cuppoletti1, J Thakkar, N Sperelakis
1Department of Physiology and Biophysics, University of Cincinnati, College of Medicine, Ohio 45267-0576.
Abstract:
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.