Phospholamban of cardiac sarcoplasmic reticulum consists of two functionally distinct proteolipids.
Phosphorylation of phospholamban by either a cAMP-dependent or a calmodulin-dependent kinase stimulates the Ca2+ transporting activity of cardiac sarcoplasmic reticulum membranes. It has now been found that phospholamban consists of 2 distinct proteins; one is the specific substrate for the cAMP-dependent phosphorylation, and the other for the calmodulin-dependent kinase. In spite of functional diversity, the 2 polypeptides share a number of properties. Among them, the proteolipid character, Mr, resistance to trypsinization, and subunit composition.
D000251:Adenosine Triphosphatases / Q000302:isolation & purification*; D000818:Animals; D002135:Calcium-Binding Proteins / Q000302:isolation & purification*; D002147:Calmodulin / Q000494:pharmacology; D002417:Cattle; D000242:Cyclic AMP / Q000494:pharmacology; D007700:Kinetics; D009206:Myocardium / Q000201:enzymology*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D011510:Proteolipids / Q000302:isolation & purification*; D051381:Rats; D012519:Sarcoplasmic Reticulum / Q000201:enzymology*; D000099211:Phospholamban
D000251:Adenosine Triphosphatases; D002135:Calcium-Binding Proteins; D002147:Calmodulin; D000242:Cyclic AMP; D011494:Protein Kinases; D011510:Proteolipids; D000099211:Phospholamban