Molecular cloning of CLC chloride channels in Oreochromis mossambicus and their functional complementation of yeast CLC gene mutant

Biochem Biophys Res Commun. 1999 Feb 5;255(1):175-81. doi: 10.1006/bbrc.1999.0166.


We have cloned two members of the CLC chloride channel family (OmCLC-3 and OmCLC-5) from gill cDNA libraries of the euryhaline tilapia Oreochromis mosammbicus. At the amino acid level, OmCLC-3 is 90.5% identical to rat CLC-3 and OmCLC-5 is 79.2% identical to rat CLC-5. Ribonuclease protection assay revealed that OmCLC-5 was mainly expressed in the gill, kidney, and intestine in both freshwater- (FW) and seawater- (SW) adapted tilapia. Although the mRNA of OmCLC-3 was broadly expressed in tissues of FW- and SW-adapted tilapia, the most intense signals were observed in the gill, kidney, intestine, and brain. Injection of OmCLC-3 and OmCLC-5 cRNAs into Xenopus oocytes did not elicit chloride currents, but these clones did functionally complement the gef1 phenotype of YPH250(gef), a yeast strain in which a single CLC channel (GEF1) has been disrupted by homologous recombination. These results clearly indicated that CLC channels closely related to the mammalian CLC-3, -4, and -5 subfamily exist also in tilapia and that OmCLC-3 and OmCLC-5 function as intracellular chloride channels.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Chloride Channels / genetics*
  • Cloning, Molecular
  • Cytokines / genetics*
  • Genes, Fungal
  • Molecular Sequence Data
  • Mutation
  • Rats
  • Saccharomyces cerevisiae
  • Sequence Alignment
  • Sequence Homology
  • Tilapia / genetics*


  • Chloride Channels
  • Cytokines
  • cardiotrophin-like cytokine

Associated data

  • GENBANK/AF182215
  • GENBANK/AF182216