A Family of Acetylcholine-gated Chloride Channel Subunits in Caenorhabditis elegans

• Published in: The Journal of biological chemistry Vol. 280; no. 8; pp. 6392 - 6398
• Main Authors: Putrenko, Igor, Zakikhani, Mahvash, Dent, Joseph A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 25.02.2005; American Society for Biochemistry and Molecular Biology
• Subjects: Animals; Arecoline - pharmacology; Base Sequence; Binding Sites; Bungarotoxins - pharmacology; Caenorhabditis elegans; Caenorhabditis elegans Proteins - chemistry; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - physiology; Chloride Channels - chemistry; Chloride Channels - genetics; Chloride Channels - physiology; Cloning, Molecular - methods; Electrophysiology; Molecular Sequence Data; Nicotine - pharmacology; Protein Subunits; Receptors, Cholinergic - chemistry; Receptors, Cholinergic - genetics; Receptors, Cholinergic - physiology; Tubocurarine - pharmacology
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M412644200

The genome of the nematode Caenorhabditis elegans encodes a surprisingly large and diverse superfamily of genes encoding Cys loop ligand-gated ion channels. Here we report the first cloning, expression, and pharmacological characterization of members of a family of anion-selective acetylcholine receptor subunits. Two subunits, ACC-1 and ACC-2, form homomeric channels for which acetylcholine and arecoline, but not nicotine, are efficient agonists. These channels are blocked by d-tubocurarine but not by α-bungarotoxin. We provide evidence that two additional subunits, ACC-3 and ACC-4, interact with ACC-1 and ACC-2. The acetylcholine-binding domain of these channels appears to have diverged substantially from the acetylcholine-binding domain of nicotinic receptors.