Cobra (Naja spp.) nicotinic acetylcholine receptor exhibits resistance to Erabu sea snake (Laticauda semifasciata) short-chain alpha-neurotoxin

Abstract. Snake a-neutotoxins of Elapidae venoms are grouped into two structural classes, short-chain and long-chain a-neutotoxins. While these two classes share many chemical and biological characteristics, there are also distinct dissimilarities between them, including their binding site on the nicotinic acetyl-choline receptor (nAChR), specificity among species of Chordata, and the associated pharmacological effects. In the present study we test the hypothesis that structural motifs that evolved to confer natural re-sistance against conspecific long-chain a-neurotoxins in Elapidae snakes also interfere with the biological action of short-chain a-neurotoxins. We expressed functional nAChRs that contains segments or single residues of the Elapidae nAChR ligand bindin