Ligand-gated chloride channels are receptors for biogenic amines in C. elegans

Science. 2009 Jul 3;325(5936):96-100. doi: 10.1126/science.1169243.


Biogenic amines such as serotonin and dopamine are intercellular signaling molecules that function widely as neurotransmitters and neuromodulators. We have identified in the nematode Caenorhabditis elegans three ligand-gated chloride channels that are receptors for biogenic amines: LGC-53 is a high-affinity dopamine receptor, LGC-55 is a high-affinity tyramine receptor, and LGC-40 is a low-affinity serotonin receptor that is also gated by choline and acetylcholine. lgc-55 mutants are defective in a behavior that requires endogenous tyramine, which indicates that this ionotropic tyramine receptor functions in tyramine signaling in vivo. Our studies suggest that direct activation of membrane chloride conductances is a general mechanism of action for biogenic amines in the modulation of C. elegans behavior.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Biogenic Amines / metabolism*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism*
  • Caenorhabditis elegans Proteins / chemistry
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Chloride Channels / chemistry
  • Chloride Channels / genetics
  • Chloride Channels / metabolism*
  • Dopamine / metabolism
  • Genes, Helminth
  • Ligands
  • Membrane Potentials / drug effects
  • Molecular Sequence Data
  • Mutant Proteins / metabolism
  • Oocytes
  • Patch-Clamp Techniques
  • Receptors, Biogenic Amine / chemistry
  • Receptors, Biogenic Amine / genetics
  • Receptors, Biogenic Amine / metabolism*
  • Serotonin / metabolism
  • Tyramine / metabolism
  • Xenopus


  • Biogenic Amines
  • Caenorhabditis elegans Proteins
  • Chloride Channels
  • LGC-40 protein, C elegans
  • LGC-53 protein, C elegans
  • LGC-55 protein, c elegans
  • Ligands
  • Mutant Proteins
  • Receptors, Biogenic Amine
  • Serotonin
  • Dopamine
  • Tyramine