title: The biochemical genetics of permethrin resistance in the Learn-PyR strain of house fly.
abstract: Permethrin resistance in the Learn-PyR strain of house fly was examined in four genetically derived substrains, each being homozygous for a different "resistant" autosome of the Learn-PyR strain. The resistance of these derivative strains was characterized toxicologically and biochemically. The relative levels of resistance to permethrin conferred by each autosome were 5 greater than 3 greater than 1 greater than 2. Three factors were associated with resistance: (1) increased mixed-function oxidase (MFO) activity associated with elevated levels of cytochrome P-450, cytochrome b5, and NADPH-cytochrome c reductase (P-450 reductase) activity; (2) target-site insensitivity (kdr); and (3) decreased cuticular penetration. Permethrin resistance factors on chromosome 1 consisted of a piperonyl butoxide (PB)-suppressible mechanism correlated with increased levels of cytochromes P-450 and b5; on chromosome 2, a PB-suppressible mechanism associated with elevated amounts of cytochrome P-450; on chromosome 3, decreased cuticular penetration, kdr, and increased amounts of P-450 reductase activity; and on chromosome 5, a largely PB-suppressible mechanism correlated with elevated levels of cytochrome P-450 and P-450 reductase activity.
authors.forename: J G
authors.initials: JG
authors.lastname: Scott
authors.forename: G P
authors.initials: GP
authors.lastname: Georghiou
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D003573:Cytochrome b Group / Q000378:metabolism; D015786:Cytochromes b5; D004175:Diptera / Q000235:genetics*; D008040:Genetic Linkage; D007305:Insecticide Resistance; D006899:Mixed Function Oxygenases / Q000235:genetics; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism; D009474:Neurons / Q000187:drug effects; D026023:Permethrin; D011722:Pyrethrins / Q000494:pharmacology*
chemical_list: D003573:Cytochrome b Group; D011722:Pyrethrins; D026023:Permethrin; D015786:Cytochromes b5; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D009251:NADPH-Ferrihemoprotein Reductase