The functional interaction between nicotinic acetylcholine receptors and Ly-6/neurotoxin proteins in Locusta migratoria.

Failures in expressing insect nAChRs (nicotinic acetylcholine receptors) limit the understanding of their functional properties, although insect nAChRs have been developed as insecticide targets for decades. Some accessory proteins can modulate nAChRs, but only a few have been identified in insects, including lynx from Ly-6/neurotoxin superfamily. Until now, only one to three lynx were identified in one insect species. Here, 11 lynx were identified in Locusta migratoria with common features of Ly-6/neurotoxin members. The effects of these lynx on seven hybrid nAChRs functionally constructed in Xenopus oocytes were tested, in which each nAChR subtype contained one L. migratoria α subunit plus rat β2 subunit. One lynx could selectively modulate several nAChR subtypes to significantly increase the amplitude of epibatidine-evoked currents, while Loc-lynx10 acted on all test nAChRs. Among nine lynx with obvious modulation effects to increase inward currents, only four significantly increased the specific [H]epibatidine binding, and the binding increase existed in all modulated nAChRs by these lynx. The results indicated that the modulation mode was decided by the specific lynx and had nothing to do with nAChR subtypes. This study provides an approximate panorama for the functional interaction net between L. migratoria lynx and nAChRs, although some other nAChRs need further tests.