Fig. 1From: Massive expansion and diversity of nicotinic acetylcholine receptors in lophotrochozoansExpansion of nAChR genes in molluscs. a Number of nAChR genes in different species. b Common domain combinations of nAChRs in different species. LBD: neurotransmitter-gated ion-channel ligand binding domain; NTM: neurotransmitter-gated ion-channel transmembrane region; TM: transmembrane domainBack to article page