Conserved SOL-1 proteins regulate ionotropic glutamate receptor desensitization.
The neurotransmitter glutamate mediates excitatory synaptic transmission by activating ionotropic glutamate receptors (iGluRs). In Caenorhabditis elegans, the GLR-1 receptor subunit is required for glutamate-gated current in a subset of interneurons that control avoidance behaviors. Current mediated by GLR-1-containing iGluRs depends on SOL-1, a transmembrane CUB-domain protein that immunoprecipitates with GLR-1. We have found that reconstitution of glutamate-gated current in heterologous cells depends on three proteins, STG-1 (a C. elegans stargazin-like protein), SOL-1, and GLR-1. Here, we use genetic and pharmacological perturbations along with rapid perfusion electrophysiological techniques to demonstrate that SOL-1 functions to slow the rate and limit the extent of receptor desensitization as well as to enhance the recovery from desensitization. We have also identified a SOL-1 homologue from Drosophila and show that Dro SOL1 has a conserved function in promoting C. elegans glutamate-gated currents. SOL-1 homologues may play critical roles in regulating glutamatergic neurotransmission in more complex nervous systems.
Walker
Craig S
CS
Department of Biology, University of Utah, Salt Lake City, UT 84112-0840, USA.
Francis
Michael M
MM
Brockie
Penelope J
PJ
Madsen
David M
DM
Zheng
Yi
Y
Maricq
Andres V
AV
D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000235:genetics; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology*; D015220:Calcium Channels / Q000737:chemistry / Q000235:genetics; D002478:Cells, Cultured; D003208:Concanavalin A / Q000378:metabolism; D017124:Conserved Sequence; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D018091:Receptors, AMPA / Q000235:genetics / Q000378:metabolism* / Q000502:physiology
C512986:CG34402 protein, Drosophila; D029742:Caenorhabditis elegans Proteins; D015220:Calcium Channels; D029721:Drosophila Proteins; D008565:Membrane Proteins; D018091:Receptors, AMPA; C481340:SOL-1 protein, C elegans; C532436:STG-2 protein, C elegans; C096470:glr-1 protein, C elegans; D003208:Concanavalin A