RECOMBINANT NEMATODE NICOTINIC RECEPTOR AND USES

摘要

The C. elegans unc-63 gene is a levamisole resistance locus on chromosome I, which encodes a nicotinic acetylcholine receptor (nAChR) alpha subunit. The derived amino acid sequence of UNC-63 most closely resembles that of UNC-38. Using a gfp: unc-63 fusion construct, expression has been detected in muscles (body wall, vulval) and motorneurons of C. elegans. Nuclear injection into Xenopus laevis oocytes of unc-63 cDNA together with lev-1 and unc-29 results in the expression of a robust functional C. elegans heteromeric nAChR. The EC50 for ACh of the expressed receptor (20 mu M) resembles that of native nematode muscle nAChRs. Nicotine and anthelmintic drug levamisole are agonists and mecamylamine is an antagonist of this expressed receptor. When unc-38 cDNA is co-injected with cDNAs encoding unc-63, lev-1 and unc-29 much smaller amplitude agonist-activated currents are observed.