title: Identification of polymorphisms in Cyrtorhinus lividipennis RDL subunit contributing to fipronil sensitivity.
abstract: As one of the most important predatory enemies, the miridbug, Cyrtorhinus lividipennis, plays an important role in rice planthoppers control, such as Nilaparvata lugens (brown planthopper). In order to compare insecticide selectivity between C. lividipennis and N. lugens, the contact acute toxicities of six insecticides (diazoxon, paraoxon, carbaryl, fenobucarb, fipronil and ethofenprox) were monitored. The results showed that all tested insecticides were more toxic to C. lividipennis than to N. lugens and fipronil had the biggest difference. The RDL subunit (Cl-RDL) was cloned from C. lividipennis and a RDL isoform (Cl-RDL-In) was also found with 31 amino acids insertion in RDL intracellular region. In order to understand the role of the insertion on insecticide sensitivities, three subunits (Nl-RDL, Cl-RDL and Cl-RDL-In) were constructed to obtain the functional receptors in Xenopus oocytes and the fipronil sensitivities were detected by the voltage-clamp technique. Nl-RDL (IC50=32.36 ± 4.07 µM) was more insensitive to fipronil than Cl-RDL (IC50=6.47 ± 1.12 µM). The insertion in Cl-RDL significantly reduced fipronil sensitivity with IC50 value in Cl-RDL-In of 16.83 ± 2.30 µM. Interestingly, after the elution of fipronil, the current response of Cl-RDL-In appeared obvious recovery, which were not observed in Cl-RDL and Nl-RDL. It might imply that the insertion played a special role in fipronil sensitivity.
authors.affiliation: Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Yixi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Huahua
authors.initials: H
authors.lastname: Sun
authors.affiliation: Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Xiangkun
authors.initials: X
authors.lastname: Meng
authors.affiliation: Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Institute of Plant Protection, Jiansu Academy of agriCultural Sciences, Nanjing 210014, China.
authors.forename: Haibo
authors.initials: H
authors.lastname: Bao
authors.affiliation: Institute of Plant Protection, Jiansu Academy of agriCultural Sciences, Nanjing 210014, China.
authors.forename: Jichao
authors.initials: J
authors.lastname: Fang
authors.affiliation: Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: liuzewen@njau.edu.cn.
authors.forename: Zewen
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D001483:Base Sequence; D002219:Carbamates / Q000633:toxicity; D012721:Carbaryl / Q000633:toxicity; D018076:DNA, Complementary / Q000235:genetics; D006430:Hemiptera / Q000187:drug effects / Q000378:metabolism; D020062:Heteroptera / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D019476:Insect Proteins / Q000235:genetics* / Q000502:physiology; D007306:Insecticides / Q000633:toxicity*; D008969:Molecular Sequence Data; D009865:Oocytes / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000633:toxicity; D010261:Paraoxon / Q000633:toxicity; D011110:Polymorphism, Genetic; D021122:Protein Subunits / Q000235:genetics* / Q000502:physiology; D011720:Pyrazoles / Q000633:toxicity; D011722:Pyrethrins / Q000633:toxicity; D011963:Receptors, GABA-A / Q000235:genetics* / Q000502:physiology; D017422:Sequence Analysis, DNA; D014981:Xenopus
chemical_list: D002219:Carbamates; D018076:DNA, Complementary; D019476:Insect Proteins; D007306:Insecticides; D009943:Organophosphorus Compounds; D021122:Protein Subunits; D011720:Pyrazoles; D011722:Pyrethrins; D011963:Receptors, GABA-A; C076840:ethofenprox; C019276:BPMC; C000912:diazoxon; D010261:Paraoxon; C082360:fipronil; D012721:Carbaryl
keywords: Cyrtorhinus lividipennis; Fipronil; RDL; Sensitivity