The C. elegans glutamate receptor subunit NMR-1 is required for slow NMDA-activated currents that regulate reversal frequency during locomotion.
The N-methyl-D-aspartate (NMDA) subtype of glutamate receptor is important for synaptic plasticity and nervous system development and function. We have used genetic and electrophysiological methods to demonstrate that NMR-1, a Caenorhabditis elegans NMDA-type ionotropic glutamate receptor subunit, plays a role in the control of movement and foraging behavior. nmr-1 mutants show a lower probability of switching from forward to backward movement and a reduced ability to navigate a complex environment. Electrical recordings from the interneuron AVA show that NMDA-dependent currents are selectively disrupted in nmr-1 mutants. We also show that a slowly desensitizing variant of a non-NMDA receptor can rescue the nmr-1 mutant phenotype. We propose that NMDA receptors in C. elegans provide long-lived currents that modulate the frequency of movement reversals during foraging behavior.
Brockie
P J
PJ
Department of Biology, University of Utah, Salt Lake City 84112, USA.
Mellem
J E
JE
Hills
T
T
Madsen
D M
DM
Maricq
A V
AV
D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D004594:Electrophysiology; D017353:Gene Deletion; D015870:Gene Expression / Q000502:physiology; D007395:Interneurons / Q000737:chemistry / Q000502:physiology; D008124:Locomotion / Q000502:physiology*; D018782:Maze Learning / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology; D008969:Molecular Sequence Data; D016296:Mutagenesis / Q000502:physiology; D010641:Phenotype; D018091:Receptors, AMPA; D017470:Receptors, Glutamate / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D009435:Synaptic Transmission / Q000502:physiology*
D029742:Caenorhabditis elegans Proteins; C436186:NMR-1 protein, C elegans; D018091:Receptors, AMPA; D017470:Receptors, Glutamate; D016194:Receptors, N-Methyl-D-Aspartate; C096470:glr-1 protein, C elegans