Conus peptides:: novel probes for nicotinic acetylcholine receptor structure and function

Conus is a genus of predatory marine snails that uses venom to capture prey. Among the neurotoxins widely utilized by the cone snails are the alpha-conotoxins which are disulfide-rich peptides that target muscle or neuronal subtypes of nicotinic acetylcholine receptors. The small size and receptor subtype specificity of these peptides make them particularly useful for characterizing both native and heterologously expressed nicotinic receptors. In this report, we demonstrate that a-conotoxin MII potently blocks beta 3-containing neuronal nicotinic receptors. Furthermore, initial evidence suggests that subpopulations of alpha 3 beta 2 beta 3-containing receptors are differentially sensitive to alpha-conotoxin MII. Thus, alpha-conotoxin MII promises to be a useful tool for studying neuronal nicotinic receptors containing the beta 3 subunit. (C) 2000 Elsevier Science B.V. All rights reserved.