ACYP2, also known as Acylphosphatase-2, is a protein which belongs to the acylphosphatase family. ACYP2 contains one acylphosphatase-like domain. ACYP2 plays an important role in hydrolyzing the phosphoenzyme intermediate of different membrane pumps, particularly the Ca2+/Mg2+-ATPase from sarcoplasmic reticulum of skeletal muscle. Two isoenzymes have been isolated, called muscle acylphosphatase and erythrocyte acylphosphatase on the basis of their tissue localization. This gene encodes the muscle-type isoform (MT). An increase of the MT isoform is associated with muscle differentiation.