title: Effect of Beauveria bassiana infection on detoxification enzyme transcription in pyrethroid resistant Anopheles arabiensis: a preliminary study.
abstract: BACKGROUND
  Fungal biopesticides are of great interest to vector control scientists as they provide a novel and environmentally friendly alternative to insecticide use. The aim of this study was to determine whether genes associated with pyrethroid resistance in Anopheles arabiensis from Sudan and South Africa are further induced following exposure to the entomopathogenic fungus, Beauveria bassiana (strain GHA).
  
  
  METHODS
  Following B. bassiana bioassays, RNA was extracted from infected mosquitoes and the transcription of four important insecticide resistance genes, CYP9L1, CYP6M2 and CYP4G16 (cytochrome P450s) and TPX4 (thioredoxin peroxidase) was investigated using quantitative real-time PCR.
  
  
  RESULTS
  Beauveria bassiana strain GHA was highly infective and virulent against An. arabiensis. In terms of changes in gene transcription, overall, the fold change (FC) values for each gene in the infected strains, were lower than 1.5. The FC values of CYP9L1, CYP6M2 and TPX4, were significantly lower than the FC values of the same genes in uninfected resistant An. arabiensis.
  
  
  CONCLUSIONS
  These data suggest that B. bassiana does not enhance the pyrethroid resistant phenotype on a molecular level as the two An. arabiensis strains used here, with different pyrethroid resistance mechanisms, revealed no increase in pre-existing metabolic transcripts. This supports the fact that fungal pathogens are suitable candidates for vector control, particularly with regard to the development of novel vector control strategies.
authors.affiliation: Vector Control Reference Laboratory, Centre for Opportunistic, Tropical and Hospital Infections, National Institute for Communicable Diseases, a Division of the National Health Laboratory Services, Private Bag X4, Sandringham, 2131, Johannesburg, South Africa.
authors.forename: Luisa
authors.initials: L
authors.lastname: Nardini
authors.forename: Simon
authors.initials: S
authors.lastname: Blanford
authors.forename: Maureen
authors.initials: M
authors.lastname: Coetzee
authors.forename: Lizette L
authors.initials: LL
authors.lastname: Koekemoer
mesh_terms: D000818:Animals; D000852:Anopheles / Q000235:genetics / Q000382:microbiology*; D052982:Beauveria; D007303:Insect Vectors / Q000382:microbiology*; D007305:Insecticide Resistance / Q000235:genetics; D007306:Insecticides; D008288:Malaria / Q000517:prevention & control*; D009032:Mosquito Control / Q000379:methods*; D026023:Permethrin; D011722:Pyrethrins / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D013019:South Africa; D013397:Sudan
chemical_list: D007306:Insecticides; D011722:Pyrethrins; D026023:Permethrin
keywords: Anopheles arabiensis; Beauveria bassiana; Detoxification, Gene expression