We found that we could reconstitute glutamate-gated currents in Xenopus oocytes or C. elegans muscle cells when s-SOL-1 was coexpressed with SOL-2, STG-1, and GLR-1 ( Figures 1E and 1F), but not in the absence of SOL-2 ( Figure 1B). Thus, s-SOL-1 function was dependent on SOL-2. Furthermore, SOL-2 cannot simply replace SOL-1 given that we were unable to reconstitute

glutamate-gated current in either oocytes or muscle cells by co-expressing GLR-1, STG-1 and SOL-2 ( Figures GSK-3 inhibitor 1E and 1F). Our reconstitution studies demonstrated that SOL-2 and SOL-1 contribute to the function of the GLR-1 signaling complex. In addition, our finding that mutations in sol-2 disrupt the behavior of transgenic lurcher mutants ( Figure 1C) predicts that glutamatergic neurotransmission is disrupted in sol-2 mutants. Thus, we Ceritinib research buy evaluated the behavior of sol-2 mutants using two standard assays that depend on GLR-1 function ( Hart et al., 1995; Maricq et al., 1995; Mellem et al., 2002). When tested in an osmotic avoidance assay the sol-2 mutants were as slow to recoil from the hyperosmotic stimuli as glr-1 or sol-1 mutants ( Figure 2A).

When tested in a touch-avoidance assay (nose touch response) sol-2 mutants were significantly impaired, but not to the extent of glr-1 or sol-1 mutants ( Figure 2B). In both assays, sol-1; sol-2 double mutants were no more impaired than sol-1 mutants alone, suggesting that the two gene products act in the same pathway. The peak amplitude of the glutamate-gated current in AVA was considerably diminished in sol-2 mutants, and we could only measure a small, rapidly activating and desensitizing current ( Figures 2C and 2D). These currents are distinct from those recorded in sol-1

mutants where we could not detect a rapidly activating inward current under the same recording conditions ( Figures 1A and 2D). Only the GLR-1-mediated current was decreased in sol-2 mutants; the slower, outwardly rectifying current is mediated by NMDA receptors ( Brockie et al., 2001b) and did not appear appreciably Urease different than wild-type current ( Figure 2C). Glutamate-gated currents in the AVA neurons of transgenic sol-2 mutants were rescued by a functional SOL-2::GFP fusion protein that was specifically expressed in AVA using the rig-3 promoter ( Feinberg et al., 2008; Figures 2C and 2D). We were also able to rescue current in transgenic sol-2 mutants that expressed GFP fused to the extracellular N terminus of full-length SOL-2 (GFP::SOL-2; Figure S2). These results demonstrate that GFP-tagged SOL-2 is functional and acts cell autonomously. However, unlike the case for SOL-1, we did not observe rescue of transgenic sol-2 mutants that expressed a secreted variant of the fusion protein that lacked the transmembrane domain (GFP::s-SOL-2) ( Figure S2).