Essential component of the Ost-alpha/Ost-beta complex, a heterodimer that acts as the intestinal basolateral transporter responsible for bile acid export from enterocytes into portal blood . Efficiently transports the major species of bile acids (taurocholate) . Taurine conjugates are transported more efficiently across the basolateral membrane than glycine-conjugated bile acids (By similarity). Can also transport steroids such as estrone 3-sulfate and dehydroepiandrosterone 3-sulfate, therefore playing a role in the enterohepatic circulation of sterols . Able to transport eicosanoids such as prostaglandin E2 (By similarity).
Subcellular locations: Cell membrane, Endoplasmic reticulum membrane
Transported from the endoplasmic reticulum to the plasma membrane upon interacting with SLC51B (By similarity). Mainly restricted to the lateral and basal membranes of ileal enterocytes.
Widely expressed with a high expression in ileum. Expressed in testis, colon, liver, small intestine, kidney, ovary and adrenal gland; and at low levels in heart, lung, brain, pituitary, thyroid gland, uterus, prostate, mammary gland and fat.