A tyramine-gated chloride channel coordinates distinct motor programs of a Caenorhabditis elegans escape response.
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.
Pirri
Jennifer K
JK
Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
McPherson
Adam D
AD
Donnelly
Jamie L
JL
Francis
Michael M
MM
Alkema
Mark J
MJ
D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D030801:Animals, Genetically Modified; D001522:Behavior, Animal; D017173:Caenorhabditis elegans / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins; D018118:Chloride Channels / Q000235:genetics / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation / Q000379:methods; D004924:Escape Reaction / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000235:genetics; D019416:Head Movements / Q000187:drug effects; D015640:Ion Channel Gating / Q000187:drug effects*; D008124:Locomotion / Q000187:drug effects / Q000235:genetics; D008564:Membrane Potentials / Q000187:drug effects / Q000235:genetics; D009154:Mutation / Q000235:genetics; D009334:Neck Muscles / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects / Q000502:physiology; D018408:Patch-Clamp Techniques; D010812:Physical Stimulation / Q000379:methods; D020539:Sequence Analysis, Protein; D014439:Tyramine / Q000494:pharmacology*; D014982:Xenopus laevis
D018759:Adrenergic Uptake Inhibitors; D029742:Caenorhabditis elegans Proteins; D018118:Chloride Channels; D049452:Green Fluorescent Proteins; D014439:Tyramine