title: Molecular characterisation of two α-esterase genes involving chlorpyrifos detoxification in the diamondback moth, Plutella xylostella.
abstract: BACKGROUND
  Carboxylesterases (CarEs) are involved in metabolic detoxification of dietary and environmental xenobiotics in insects. However, owing to the complexity of the protein family, the involvement of CarEs in insecticide metabolism in Plutella xylostella has not been fully elucidated. This study aimed to characterise two CarE genes and assess their potential roles in response to chlorpyrifos in P. xylostella.
  
  
  RESULTS
  Synergistic tests showed that triphenyl phosphate decreased the resistance of the third-instar larvae to chlorpyrifos. The treatment of the third-instar larvae with chlorpyrifos at the LC30dose led to a significant increase in CarE activity. Two CarE cDNAs (Pxae18 and Pxae28) were subsequently sequenced and characterised. Both genes were expressed predominantly in the larval midgut. Most importantly, two CarE genes showed significantly higher expression in the chlorpyrifos-resistant strain than in the susceptible strain. RNAi knockdown of Pxae18 and Pxae28 significantly increased the mortality to chlorpyrifos from 40% in the control to 73.8 and 63.3% respectively.
  
  
  CONCLUSIONS
  RNAi knockdown of Pxae18 and Pxae28 significantly inhibited detoxification ability and increased the mortality in P. xylostella. The results indicate that these two CarE genes play important roles in the detoxification of chlorpyrifos in P. xylostella. © 2016 Society of Chemical Industry.
authors.affiliation: Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.|College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China.|Fujian-Taiwan Joint Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, China.|Key Laboratory of Integrated Pest Management of Fujian and Taiwan, China Ministry of Agriculture, Fuzhou, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Xie
authors.affiliation: Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.|Fujian-Taiwan Joint Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, China.|Key Laboratory of Integrated Pest Management of Fujian and Taiwan, China Ministry of Agriculture, Fuzhou, China.
authors.forename: Na-Na
authors.initials: NN
authors.lastname: Ren
authors.affiliation: Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.|College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China.|Fujian-Taiwan Joint Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, China.|Key Laboratory of Integrated Pest Management of Fujian and Taiwan, China Ministry of Agriculture, Fuzhou, China.
authors.forename: Yan-Chun
authors.initials: YC
authors.lastname: You
authors.affiliation: Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.|College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China.|Fujian-Taiwan Joint Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, China.|Key Laboratory of Integrated Pest Management of Fujian and Taiwan, China Ministry of Agriculture, Fuzhou, China.
authors.forename: Wei-Jun
authors.initials: WJ
authors.lastname: Chen
authors.affiliation: College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China.|Division of Plant Sciences, University of Missouri, Columbia, MO, USA.
authors.forename: Qi-Sheng
authors.initials: QS
authors.lastname: Song
authors.affiliation: Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.|Fujian-Taiwan Joint Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, China.|Key Laboratory of Integrated Pest Management of Fujian and Taiwan, China Ministry of Agriculture, Fuzhou, China.
authors.forename: Min-Sheng
authors.initials: MS
authors.lastname: You
mesh_terms: D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000235:genetics* / Q000378:metabolism; D004390:Chlorpyrifos / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D008658:Inactivation, Metabolic; D007306:Insecticides / Q000378:metabolism*; D007814:Larva / Q000235:genetics / Q000378:metabolism; D009036:Moths / Q000235:genetics* / Q000378:metabolism; D010755:Organophosphates / Q000494:pharmacology; D034622:RNA Interference
chemical_list: D007306:Insecticides; D010755:Organophosphates; D002265:Carboxylic Ester Hydrolases; D004390:Chlorpyrifos; C005445:triphenyl phosphate
keywords: Plutella xylostella; RNAi; carboxylesterase; insecticide detoxification