1.A.9.1.21
Nicotinic acetylcholine receptor, nAChR with 4 subunits, Alpha1, 2, and 3 as well as beta1.  Bradysia odoriphaga is a destructive insect pest, damaging more than 30 crop species. Nicotinic acetylcholine receptors (nAChRs) mediating fast excitatory transmission in the central nervous systems in insects are the molecular targets of some economically important insecticides including imidacloprid, which has been widely used to control B. odoriphaga in China since 2013. Shan et al. 2020 cloned seven nAChR subunit genes from B. odoriphaga, including Boα1, Boα2, Boα3, Boα7, Boα8, Boβ1 and Boβ3. They resemble the Drosophila melanogaster nAChR alpha1 subunit, including an extracellular N-terminal domain containing six functional loops (loop A-F), a signature Cys-loop with two disulfide bond-forming cysteines separated by 13 amino acid residues, and four typical TMSs 1 - 4) in the C-terminal region. Four of these subunits are included in TCDB. The nicotinic acetylcholine receptor nAChR, is involved in immune regulation in pearl oysters (Pinctada fucata martensii). Neonicotinoids are selective modulators of insect nAChRs. These insecticides interact with the orthosteric sites of nAChRs, not only to activate nAChRs, but also to block the desensitizing component of nAChR responses. Recombinant vertebrate and insect/vertebrate hybrid nAChRs have been deployed to understand the mechanism of selectivity and diversity of neonicotinoid actions as well as to show that both alpha/alpha and alpha/non-alpha interfaces are involved in the interactions with neonicotinoids (Matsuda 2021).