α-Conotoxin BuIA

α-Conotoxin BuIA is a paralytic peptide neurotoxin and a competitive nAChR antagonist, with IC50s of 0.258 nM (α6/α3β2), 1.54 nM (α6/α3β4), 5.72 nM (α3β2), respectively. α-Conotoxin BuIA can be used to distinguish nAChRs containing β2- and β4-subunit, respectively. α-Conotoxin BuIA distinguishes among αxβ2 nAChRs with a rank order potency of α6>α3>α2>α4[1].

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[1]Azam L, et al. Alpha-conotoxin BuIA, a novel peptide from Conus bullatus, distinguishes among neuronal nicotinic acetylcholine receptors. J Biol Chem. 2005 Jan 7;280(1):80-7.