Involved in teeth and skeletal development. Has an essential role in the biosynthesis and trafficking of glycosaminoglycans and glycoproteins, to produce a proper functioning extracellular matrix. Required for extracellular matrix mineralization (, ). Also involved in the regulation of cellular calcium homeostasis (, ). Does not show transport activity towards bile acids or steroid sulfates (including taurocholate, cholate, chenodeoxycholate, estrone-3-sulfate, dehydroepiandrosterone sulfate (DHEAS) and pregnenolone sulfate).
Subcellular locations: Cell membrane, Endoplasmic reticulum membrane, Golgi apparatus membrane
Widely expressed (, ). Expressed at high levels in liver and at lower levels in prostate, placenta, kidney, heart, lung, thymus and spleen (, ). Strongly expressed in testis and also detected in brain, ovary, colon and small intestine . Weakly expressed in testis and not detected in brain, ovary, colon or small intestine . Isoform 1: Expressed in liver, testis and placenta . Isoform 4: Expressed in liver, testis and placenta .