Mutations of acetylcholinesterase1 contribute to prothiofos-resistance in Plutella xylostella (L.).
Insensitive acetylcholinesterase (AChE) is involved in the resistance of organophosphorous and carbamate insecticides. We cloned a novel full-length AChE cDNA encoding ace1 gene from adult heads of the diamondback moth (DBM, Plutella xylostella). The ace1 gene encoding 679 amino acids has conserved motifs including catalytic triad, choline-binding site and acyl pocket. Northern blot analysis revealed that the ace1 gene was expressed much higher than the ace2 in all examined body parts. The biochemical properties of expressed AChEs showed substrate specificity for acetylthiocholine iodide and inhibitor specificity for BW284C51 and eserine. Three mutations of AChE1 (D229G, A298S, and G324A) were identified in the prothiofos-resistant strain, two of which (A298S and G324A) were expected to be involved in the prothiofos-resistance through three-dimensional modeling. In vitro functional expression of AChEs in Sf9 cells revealed that only resistant AChE1 is less inhibited with paraoxon, suggesting that resistant AChE1 is responsible for prothiofos-resistance.
Lee
Dae-Weon
DW
Ilsong Institute of Life Science, Hallym University, Anyang 431-060, Republic of Korea.
Choi
Jae Young
JY
Kim
Won Tae
WT
Je
Yeon Ho
YH
Song
Jong Tae
JT
Chung
Bu Keun
BK
Boo
Kyung Saeng
KS
Koh
Young Ho
YH
D000110:Acetylcholinesterase / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D002093:Benzenaminium, 4,4'-(3-oxo-1,5-pentanediyl)bis(N,N-dimethyl-N-2-propenyl-), Dibromide / Q000494:pharmacology; D002800:Cholinesterase Inhibitors; D007305:Insecticide Resistance / Q000235:genetics*; D008969:Molecular Sequence Data; D009036:Moths / Q000187:drug effects / Q000235:genetics*; D063086:Organothiophosphates / Q000494:pharmacology*; D010261:Paraoxon / Q000494:pharmacology; D010640:Phenothiazines / Q000494:pharmacology; D010830:Physostigmine / Q000494:pharmacology; D013379:Substrate Specificity
D002800:Cholinesterase Inhibitors; D063086:Organothiophosphates; D010640:Phenothiazines; D002093:Benzenaminium, 4,4'-(3-oxo-1,5-pentanediyl)bis(N,N-dimethyl-N-2-propenyl-), Dibromide; C084820:profenamine; D010830:Physostigmine; D000110:Acetylcholinesterase; C032072:prothiophos; D010261:Paraoxon