SLCO1B3

Source: NCBI Gene, accessed 2026-10-07.

Protein

Solute carrier organic anion transporter family member 1B3

Function (excerpt)

Mediates the Na(+)-independent uptake of organic anions. Shows broad substrate specificity, can transport both organic anions such as bile acid taurocholate (cholyltaurine) and conjugated steroids (17-beta-glucuronosyl estradiol, dehydroepiandrosterone sulfate (DHEAS), and estrone 3-sulfate), as well as eicosanoid leukotriene C4, prostaglandin E2 and L-thyroxine (T4). Hydrogencarbonate/HCO3(-) acts as the probable counteranion that exchanges for organic anions. Shows a pH-sensitive substrate specificity towards sulfated steroids, taurocholate and T4 which may be ascribed to the protonation state of the binding site and leads to a stimulation of substrate transport in an acidic microenvironment. Involved in the clearance of bile acids and organic anions from the liver. Can take up bilirubin glucuronides from plasma into the liver, contributing to the detoxification-enhancing liver-blood shuttling loop.

Subcellular location

Basolateral cell membrane; Basal cell membrane.

Tissue specificity

Highly expressed in liver, in particular at the basolateral membrane of hepatocytes near the central vein. Expressed in the placenta. In testis, primarily localized to the basal membrane of Sertoli cells and weakly expressed in Leydig cells and within the tubules.

Associated conditions

Hyperbilirubinemia, Rotor type (HBLRR).

Source: UniProtKB/Swiss-Prot Q9NPD5, release 2026_03, licensed CC BY 4.0. This is the protein’s normal biology, not evidence about post-drug syndromes; associated conditions are inherited disorders of the gene, not PFS, PSSD or PRSD.

Written for the whole drug transporters family, not for SLCO1B3 specifically.