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Updated: Dec 27, 2025

Functional Characterization of Carboxylesterases in Insecticide Resistant House Flies, Musca Domestica
Published on: August 23, 2018
Functional Characterization of Two Carboxylesterase Genes Involved in Pyrethroid Detoxification in Helicoverpa
Yong-Qiang Li1, Li-Sha Bai1, Cai-Xia Zhao1
1State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
Abstract:
Insect carboxylesterases are major enzymes involved in metabolism of xenobiotics including insecticides. Two carboxylesterase genes, CarE001A and CarE001H, were cloned from the destructive agricultural pest Helicoverpa armigera. Quantitative real-time polymerase chain reaction showed that CarE001A and CarE001H were predominantly expressed in fat body and midgut, respectively; developmental expression analyses found that the expression levels of both CarEs were significantly higher in fifth-instar larvae than in other life stages. Recombinant CarE001A and CarE001H expressed in the Escherichia coli exhibited high enzymatic activity toward α-naphthyl acetate. Inhibition assays showed that organophosphates had strong inhibition on CarEs activity compared to pyrethroids. Metabolism assays indicated that CarE001A and CarE001H were able to metabolize β-cypermethrin and λ-cyhalothrin. Homology modeling and molecular docking analyses demonstrated that β-cypermethrin could fit nicely into the active pocket of both carboxylesterases. These results suggested that CarE001A and CarE001H could play important roles in the detoxification of pyrehtroids in H. armigera.
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