Molecular origin of plasma membrane citrate transporter in human prostate epithelial cells

EMBO Rep. 2010 Jun;11(6):431-7. doi: 10.1038/embor.2010.51. Epub 2010 May 7.


The prostate is a highly specialized mammalian organ that produces and releases large amounts of citrate. However, the citrate release mechanism is not known. Here, we present the results of molecular cloning of a citrate transporter from human normal prostate epithelial PNT2-C2 cells shown previously to express such a mechanism. By using rapid amplification of cDNA ends PCR, we determined that the prostatic carrier is an isoform of the mitochondrial transporter SLC25A1 with a different first exon. We confirmed the functionality of the clone by expressing it in human embryonic kidney cells and performing radiotracer experiments and whole-cell patch-clamp recordings. By using short interfering RNAs targeting different parts of the sequence, we confirmed that the cloned protein is the main prostatic transporter responsible for citrate release. We also produced a specific antibody and localized the cloned transporter protein to the plasma membrane of the cells. By using the same antibody, we have shown that the cloned transporter is expressed in non-malignant human tissues.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Anion Transport Proteins / chemistry
  • Anion Transport Proteins / metabolism
  • Biological Transport
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Cell Line
  • Cell Membrane / metabolism*
  • Citric Acid / metabolism
  • Epithelial Cells / cytology
  • Epithelial Cells / metabolism*
  • Evolution, Molecular*
  • Gene Silencing
  • Humans
  • Immunohistochemistry
  • Ions / metabolism
  • Male
  • Mitochondrial Proteins / chemistry
  • Mitochondrial Proteins / metabolism
  • Molecular Sequence Data
  • Organic Anion Transporters
  • Prostate / cytology*
  • Protein Isoforms / chemistry
  • Protein Isoforms / metabolism


  • Anion Transport Proteins
  • Carrier Proteins
  • Ions
  • Mitochondrial Proteins
  • Organic Anion Transporters
  • Protein Isoforms
  • Slc25a1 protein, human
  • citrate-binding transport protein
  • Citric Acid

Associated data

  • GENBANK/HM037273