Cloning, functional characterization, and localization of a rat renal Na+-dicarboxylate transporter

Am J Physiol. 1998 Aug;275(2):F298-305. doi: 10.1152/ajprenal.1998.275.2.F298.


We report here the isolation, functional characterization, tissue distribution, and membrane localization of rat renal Na+-dicarboxylate transporter (rNaDC-1). rNaDC-1 consists of 2,245 nucleotides, and the deduced amino acid sequence showed 73% and 75% identity to rabbit and human NaDC-1, respectively. When expressed in Xenopus laevis oocytes, rNaDC-1 mediated sodium-dependent uptake of di- and tricarboxylates. Substrates of rNaDC-1 evoked inward currents in oocytes expressed with rNaDC-1; succinate, alpha-ketoglutarate, and glutarate were relatively high-affinity substrates, and citrate was a low-affinity substrate of rNaDC-1. The coupling ratio of citrate to charge was determined to be 1:1 at pH 7.4; influx of one positive charge per citrate molecule suggests a symport of three Na+ with a divalent citrate. Expression of rNaDC-1 mRNA was detected in the kidney and the small and large intestines. Immunohistochemistry using polyclonal antibodies raised against the 14 amino acids at the COOH terminus of rNaDC-1 revealed that rNaDC-1 is localized exclusively in the luminal membrane of S2 and S3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Biological Transport / drug effects
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics*
  • Carrier Proteins / metabolism
  • Cell Membrane / metabolism
  • Cloning, Molecular
  • DNA, Complementary
  • Dicarboxylic Acid Transporters*
  • Dicarboxylic Acids / pharmacology
  • Gene Library
  • Humans
  • Kidney / metabolism*
  • Kidney Cortex / metabolism
  • Kidney Medulla / metabolism
  • Kinetics
  • Membrane Proteins / chemistry
  • Membrane Proteins / genetics*
  • Membrane Proteins / metabolism
  • Molecular Sequence Data
  • Organic Anion Transporters, Sodium-Dependent*
  • Rabbits
  • Rats
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Succinates / metabolism
  • Symporters*
  • Tricarboxylic Acids / pharmacology


  • Carrier Proteins
  • DNA, Complementary
  • Dicarboxylic Acid Transporters
  • Dicarboxylic Acids
  • Membrane Proteins
  • Organic Anion Transporters, Sodium-Dependent
  • Recombinant Proteins
  • SLC13A2 protein, human
  • Slc13a2 protein, rat
  • Succinates
  • Symporters
  • Tricarboxylic Acids