The inhibitory effect of phospholemman on the sodium pump requires Its palmitoylation

Background: Phospholemman regulates the plasmalemmal sodium pump in excitable tissues such as the heart.Results: Phospholemman is palmitoylated at two intracellular cysteines, and this reduces ion transport by the sodium pump.Conclusion: Phospholemman must be palmitoylated to inhibit the sodium pump.Significance: This is a potentially new way to regulate the sodium pump, an enzyme expressed in most eukaryotic cells.