title: Cloning and overexpression of CYP6F1, a cytochrome P450 gene, from deltamethrin-resistant Culex pipiens pallens.
abstract: CYP6F1 (GenBank/EMBL accession No. AY662654), a novel gene with a complete encoding sequence in the cytochrome P450 family 6, was cloned and sequenced from deltamethrin-resistant 4th instar larvae of Culex pipiens pallens. The cDNA sequence of CYP6F1 has an open reading frame of 1527 bp, which encodes a putative protein of 508 amino acid residues. The deduced amino acid sequence of CYP6F1 indicated that the encoded P450 has conserved domains of a putative membrane-anchoring signal, putative reductase-binding sites, a typical heme-binding site, an ETLR motif and substrate recognition sites. Semi-quantitative RT-PCR analysis indicated that the CYP6F1 gene was expressed to a greater extent in the deltamethrin-resistant strain than in the susceptible strain of Cx. pipiens pallens. The expression levels of the CYP6F1 gene in the deltamethrin-resistant 1st, 2nd, 3rd, 4th instar larvae and adult female mosquitoes differed, with highest expression levels in the 4th instar larvae. In addition, the CYP6F1 gene was stably expressed in mosquito C6/36 cells, and the expected 61.2 kDa band was identified by Western blotting. The cells transfected with CYP6F1 had an increased resistance to deltamethrin as compared with control cells. These results indicate that CYP6F1 is expressed at higher levels in the deltamethrin-resistant strain, and may confer some insecticide resistance in Cx. pipiens pallens.
authors.affiliation: Department of Pathogenic Biology, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Mao-Qing
authors.initials: MQ
authors.lastname: Gong
authors.forename: Yan
authors.initials: Y
authors.lastname: Gu
authors.forename: Xiao-Bang
authors.initials: XB
authors.lastname: Hu
authors.forename: Yan
authors.initials: Y
authors.lastname: Sun
authors.forename: Lei
authors.initials: L
authors.lastname: Ma
authors.forename: Xiu-Lan
authors.initials: XL
authors.lastname: Li
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Sun
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.forename: Jin
authors.initials: J
authors.lastname: Qian
authors.forename: Chang-Liang
authors.initials: CL
authors.lastname: Zhu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003001:Cloning, Molecular / Q000379:methods; D003465:Culex / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000072472:Cytochrome P450 Family 6; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D007113:Immunity, Innate; D019476:Insect Proteins; D007306:Insecticides / Q000494:pharmacology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009570:Nitriles / Q000494:pharmacology*; D010105:Oxygenases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015202:Protein Engineering / Q000379:methods*; D011722:Pyrethrins / Q000494:pharmacology*; D017386:Sequence Homology, Amino Acid
chemical_list: D019476:Insect Proteins; D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin; D003577:Cytochrome P-450 Enzyme System; D010105:Oxygenases; C406279:CYP6F1 protein, Culex pipiens pallens; D000072472:Cytochrome P450 Family 6