alpha-Conotoxin LtIA. A Novel Blocker of alpha3/beta2 nAChR.
alpha-Conotoxin LtIA is a 16 amino acid peptidyl toxin isolated from the Conus litteratus (Lettered cone) venom.
It belongs to the alpha-Conotoxin superfamily, although it lacks the highly conserved Ser-Xaa-Pro sequence. It reversibly blocks alpha3/beta2 nicotinic ACh channel receptor with an IC50 of 9.8 nM.
Little or no block was obtained by 10 fold concentrations of the toxin on alpha4/beta2 and alpha3/beta4 nicotinic ACh receptors.
alpha -Conotoxin LtIA was substantially less potent on alpha6/alpha3/beta4 versus alpha6/alpha3/beta2/beta3 nAChRs. In contrast, there was little or no block by alpha-Conotoxin LtIA at 10 μM on other nAChR, including alpha1/beta1/delta/epsilon, alpha2/beta2, alpha2/beta4, alpha4/beta2, alpha4/beta4, alpha7, and alpha9alpha10.
Ion Channel Modulators; Nicotinic Acetylcholine Receptor Blockers