Functional characterization of the mouse organic-anion-transporting polypeptide 2

Biochim Biophys Acta. 2002 Aug 19;1564(1):183-8. doi: 10.1016/s0005-2736(02)00445-5.


We have isolated and functionally characterized an additional murine member of the organic-anion-transporting polypeptide (Oatp) family of membrane transport proteins from mouse liver. The 3.6 kb cDNA insert contains an open reading frame of 2010 bp coding for a 670 amino acid protein. Based on its amino acid identity of 88% to the rat Oatp2, it is considered the mouse Oatp2 orthologue. Functional expression in Xenopus laevis oocytes demonstrated that mouse Oatp2 transports several general Oatp substrates such as estrone-3-sulfate, dehydroepiandrosterone sulfate (DHEAS), ouabain and BQ-123 but hardly any taurocholate nor rocuronium or deltorphin II. The high-affinity rat Oatp2 substrate digoxin is transported with a rather low affinity with an apparent K(m) value of 5.7 microM. Bromosulfophthalein (BSP), a substrate not transported by the rat Oatp2, is transported very well by mouse Oatp2. Northern blot analysis demonstrated a predominant expression in the liver with additional signals in kidney and brain. Using fluorescence in situ hybridization, the Oatp2 gene (gene symbol Slc21a5) was mapped to chromosome 6G1-G3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Chromosome Mapping
  • DNA, Complementary / genetics
  • Female
  • In Situ Hybridization, Fluorescence
  • Kinetics
  • Male
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism*
  • Mice
  • Molecular Sequence Data
  • Oocytes / metabolism
  • Organic Anion Transporters / genetics
  • Organic Anion Transporters / metabolism*
  • Organic Cation Transport Proteins*
  • Rats
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Tissue Distribution
  • Xenopus laevis


  • DNA, Complementary
  • Membrane Transport Proteins
  • Oatp2 protein, mouse
  • Organic Anion Transporters
  • Organic Cation Transport Proteins
  • Recombinant Proteins