The role of alkaline phosphatase in mineralization

Purpose of review: Alkaline phosphatase is an important component in hard tissue formation, highly expressed in mineralized tissue cells. It is appropriate to review the current status of this important enzyme. Recent findings: The mechanism with which this enzyme carries out its function is not completely understood, but it appears to act both to increase the local concentration of inorganic phosphate, a mineralization promoter, and to decrease the concentration of extracellular pyrophosphate, an inhibitor of mineral formation. The enzyme is localized to the outside of the plasma membrane of cells, and of the membrane of matrix vesicles. It is attached to the membrane by a glycophosphatidylinositol anchor,…