Molecular characterization of taurine transport in bovine aortic endothelial cells

Biochim Biophys Acta. 2000 Dec 20;1509(1-2):324-34. doi: 10.1016/s0005-2736(00)00315-1.


Cultured bovine aortic endothelial (BAE) cells expressed a Na(+)/Cl(-)-dependent taurine uptake activity that saturated with an apparent K(0.5) of approximately 4.9 microM for taurine and was inhibited by beta-alanine, guanidinoethane sulfonate, and homotaurine. We isolated a taurine transporter clone from a BAE cell cDNA library that revealed >91% sequence identity at the amino acid level to the previously cloned high-affinity mammalian taurine transporters. The biochemical and pharmacological properties of the bovine taurine transporter cDNA expressed in Xenopus oocyte was similar to those of the high-affinity taurine transporter. Surprisingly, F(-) blocked taurine uptake in BAE cells with an IC(50) of approximately 17.5 mM. The endogenous taurine uptake was also inhibited by the protein kinase C activator phorbol 12-myristate 13-acetate, but not by its inactive analog, 4 alpha-phorbol 12,13-didecanoate. The endogenous uptake was stimulated, however, by hypertonic stress and the increase was due to an increase in the V(max) of taurine uptake. Our results provide the first description of a molecular mechanism that may be responsible for maintaining the intracellular taurine content in the endothelial cells.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Aorta
  • Biological Transport
  • Calcimycin / pharmacology
  • Carrier Proteins / biosynthesis
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cattle
  • Cells, Cultured
  • DNA, Complementary / biosynthesis
  • Endothelium, Vascular / drug effects
  • Endothelium, Vascular / metabolism*
  • Genetic Vectors
  • Membrane Glycoproteins / biosynthesis
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Membrane Transport Proteins*
  • Molecular Sequence Data
  • Oocytes / metabolism
  • Phorbol Esters / pharmacology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Alignment
  • Sodium Chloride / pharmacology
  • Taurine / metabolism*
  • Tritium
  • Xenopus


  • Carrier Proteins
  • DNA, Complementary
  • Membrane Glycoproteins
  • Membrane Transport Proteins
  • Phorbol Esters
  • Tritium
  • taurine transporter
  • Taurine
  • Calcimycin
  • Sodium Chloride