Phospholamban Adenovirus (Ad-Phospholamban)

Phospholamban (PLB, sarco (endo) plasmic-reticulum (SER) regulatory protein) is a 52 amino acid phospho-protein that assembles into a pentamer in the plasma membrane of SER cardiac, smooth and slow-twitch muscle. PLB may regulate cardiac contractility through modulation of SER Ca2+ ATPase (SERCA2a) . Nonphosphorylated PLB binds to SERCA2a and inhibits Ca2+ re-uptake into the SER. Phosphorylation of PLB causes dissociation from SERCA2a, allowing Ca2+ uptake into the SER and subsequent ventricular relaxation.