ATP2A3

Sarcoplasmic/endoplasmic reticulum calcium ATPase 3 is an enzyme that in humans is encoded by the ATP2A3 gene.

This gene encodes one of the SERCA Ca²⁺-ATPases, which are intracellular pumps located in the sarcoplasmic or endoplasmic reticula of cells. SERCA3 expression was originally described as non-muscular, but was recently observed in cardiomyocyte. This enzyme catalyzes the hydrolysis of ATP coupled with the translocation of calcium from the cytosol to the sarcoplasmic reticulum lumen, and is involved in calcium sequestration associated with muscular excitation and contraction. Alternative splicing results in 6 transcript variants encoding different isoforms named SERCA3a to SERCA3f.