Association of neonicotinoid insensitivity with a conserved residue in the loop d binding region of the tick nicotinic acetylcholine receptor.
Neonicotinoid insecticides target nicotinic acetylcholine receptors (nAChR) in the nervous system of insects but are largely ineffective against ticks. This study aimed to identify the molecular basis for this insensitivity. A homology model of the nAChR binding domain was generated on the basis of the crystal structure of an acetylcholine-binding protein with the insecticide imidacloprid bound. We hypothesized that tick β-subunits would differ at a critical residue (Arg81) in their D loops. To test this, we sequenced nAChR genes from five tick species and found that instead of the conserved arginine found in insects, a glutamine was present in all the tick sequences.
Department of Crystallography, Birkbeck College, University of London , London, UK.
Laura
L
Erdmanis
Andrias O
AO
O'Reilly
Martin S
MS
Williamson
Linda M
LM
Field
Andreas
A
Turberg
B A
BA
Wallace
D056810:Acaricides / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D007305:Insecticide Resistance; D008958:Models, Molecular; D008967:Molecular Biology; D009525:Niacin / Q000031:analogs & derivatives*; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011978:Receptors, Nicotinic / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013987:Ticks / Q000187:drug effects / Q000378:metabolism*
D056810:Acaricides; D011978:Receptors, Nicotinic; D009525:Niacin