Species Human Entrez 6554 | Human Mouse Ensembl ENSG00000100652 | |
 | ||
Aliases SLC10A1, NTCP, solute carrier family 10 member 1 External IDs MGI: 97379 HomoloGene: 31126 GeneCards: SLC10A1 | ||
Sodium/bile acid cotransporter also known as the Na+-taurocholate cotransporting polypeptide (NTCP) or liver bile acid transporter (LBAT) is a protein that in humans is encoded by the SLC10A1 (solute carrier family 10 member 1) gene.
Contents
Structure
Sodium/bile acid cotransporters are integral membrane glycoproteins. Human NTCP contains 349 amino acids and has a mass of 56 kDa.
Function
Bile acid:sodium symporters participate in the enterohepatic circulation of bile acids. Two homologous transporters are involved in the reabsorption of bile acids. One of these absorbs bile acids from the intestinal lumen, the bile duct, and the kidney with an apical localization (ileal sodium/bile acid cotransporter). The other is this protein and is expressed in the basolateral membranes of hepatocytes (NTCP).
As a cotransporter, NTCP binds two sodium ions and one (conjugated) bile salt molecule, thereby providing an hepatic influx of bile salts. Other transported molecules include steroid hormones, thyroid hormones and various xenobiotics:
Hepatitis virus entry
NTCP is a cell surface receptor necessary for the entry of hepatitis B and hepatitis D virus. This entry mechanism is inhibited by myrcludex B, cyclosporin A, progesterone, propranolol, bosentan, ezetimibe, as well as NTCP substrates like taurocholate, tauroursodeoxycholate and bromosulfophthalein.