title: eat-2 and eat-18 are required for nicotinic neurotransmission in the Caenorhabditis elegans pharynx.
abstract: Mutations in eat-2 and eat-18 cause the same defect in C. elegans feeding behavior: the pharynx is unable to pump rapidly in the presence of food. EAT-2 is a nicotinic acetylcholine receptor subunit that functions in the pharyngeal muscle. It is localized to the synapse between pharyngeal muscle and the main pharyngeal excitatory motor neuron MC, and it is required for MC stimulation of pharyngeal muscle. eat-18 encodes a small protein that has no homology to previously characterized proteins. It has a single transmembrane domain and a short extracellular region. Allele-specific genetic interactions between eat-2 and eat-18 suggest that EAT-18 interacts physically with the EAT-2 receptor. While eat-2 appears to be required specifically for MC neurotransmission, eat-18 also appears to be required for the function of other nicotinic receptors in the pharynx. In eat-18 mutants, the gross localization of EAT-2 at the MC synapse is normal, suggesting that it is not required for trafficking. These data indicate that eat-18 could be a novel component of the pharyngeal nicotinic receptor.
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9148, USA. jim@eatworms.swmed.edu
authors.forename: James P
authors.initials: JP
authors.lastname: McKay
authors.forename: David M
authors.initials: DM
authors.lastname: Raizen
authors.forename: Alexander
authors.initials: A
authors.lastname: Gottschalk
authors.forename: William R
authors.initials: WR
authors.lastname: Schafer
authors.forename: Leon
authors.initials: L
authors.lastname: Avery
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002038:Bungarotoxins / Q000378:metabolism; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000502:physiology*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018509:DNA, Helminth / Q000235:genetics; D017238:Genes, Helminth; D008969:Molecular Sequence Data; D009046:Motor Neurons / Q000502:physiology; D009154:Mutation; D010609:Pharyngeal Muscles / Q000294:innervation / Q000502:physiology; D010614:Pharynx / Q000294:innervation / Q000502:physiology; D011978:Receptors, Nicotinic / Q000235:genetics* / Q000502:physiology*; D009435:Synaptic Transmission
chemical_list: D002038:Bungarotoxins; D029742:Caenorhabditis elegans Proteins; D018076:DNA, Complementary; D018509:DNA, Helminth; C487508:Eat-2 protein, C elegans; D011978:Receptors, Nicotinic