A tyramine-gated chloride channel coordinates distinct motor programs of a Caenorhabditis elegans escape response

Neuron. 2009 May 28;62(4):526-38. doi: 10.1016/j.neuron.2009.04.013.


A key feature of escape responses is the fast translation of sensory information into a coordinated motor output. In C. elegans, anterior touch initiates a backward escape response in which lateral head movements are suppressed. Here, we show that tyramine inhibits head movements and forward locomotion through the activation of a tyramine-gated chloride channel, LGC-55. lgc-55 mutant animals have defects in reversal behavior and fail to suppress head oscillations in response to anterior touch. lgc-55 is expressed in neurons and muscle cells that receive direct synaptic inputs from tyraminergic motor neurons. Therefore, tyramine can act as a classical inhibitory neurotransmitter. Activation of LGC-55 by tyramine coordinates the output of two distinct motor programs, locomotion and head movements that are critical for a C. elegans escape response.

Publication types

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

MeSH terms

  • Adrenergic Uptake Inhibitors / pharmacology*
  • Analysis of Variance
  • Animals
  • Animals, Genetically Modified
  • Behavior, Animal
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins
  • Chloride Channels / genetics
  • Chloride Channels / physiology*
  • Dose-Response Relationship, Drug
  • Electric Stimulation / methods
  • Escape Reaction / physiology*
  • Gene Expression / drug effects
  • Green Fluorescent Proteins / genetics
  • Head Movements / drug effects
  • Ion Channel Gating / drug effects*
  • Locomotion / drug effects
  • Locomotion / genetics
  • Membrane Potentials / drug effects
  • Membrane Potentials / genetics
  • Mutation / genetics
  • Neck Muscles / metabolism
  • Oocytes / drug effects
  • Oocytes / physiology
  • Patch-Clamp Techniques
  • Physical Stimulation / methods
  • Sequence Analysis, Protein
  • Tyramine / pharmacology*
  • Xenopus laevis


  • Adrenergic Uptake Inhibitors
  • Caenorhabditis elegans Proteins
  • Chloride Channels
  • Green Fluorescent Proteins
  • Tyramine