Alpha-conotoxins bind to the nicotinic acetylcholine receptors (nAChR) and inhibit them. This peptide potently blocks muscular nicotinic acetylcholine receptor (CHRNA1-CHRNB1-CHRNG-CHRND), and has no effect on neuronal receptors. It is able to totally displace [125I]-Bgtx from the Torpedo receptor with an inhibition constant (Ki) of 2.2 and 0.7 nM. Expressed by the venom duct. Belongs to the conotoxin A superfamily.