Related Experiment Videos
Cyclic GMP-dependent protein kinase phosphorylates phospholamban in isolated sarcoplasmic reticulum from cardiac and
L Raeymaekers1, F Hofmann, R Casteels
1Laboratory of Physiology, University of Leuven, Belgium.
The Biochemical Journal
|May 15, 1988
Abstract:
Phospholamban of isolated sarcoplasmic reticulum of cardiac and smooth muscle is phosphorylated by cyclic GMP-dependent protein kinase (G-kinase). Concomitantly, the affinity of the Ca2+ pump for Ca2+ is increased. These effects are very similar to those seen with cyclic AMP-dependent protein kinase (A-kinase). The phosphate incorporation into phospholamban and the stimulatory effects of both kinases on the Ca2+ pump are not additive, suggesting that G-kinase phosphorylates the same serine residue as A-kinase. A possible physiological role for phosphorylation of phospholamban by G-kinase is discussed.