Medical and Veterinary Entomology (2008) 22, 48-54

D. Porretta, M. Gargani, R. Bellini, A. Medici, F. Punelli and S. Urbanelli (2008)
Defence mechanisms against insecticides temephos and diflubenzuron in the mosquito Aedes caspius: the P-glycoprotein efflux pumps
Medical and Veterinary Entomology 22 (1), 48-54
Abstract: P-glycoproteins (P-gps) are efflux transporters found in cells of a broad range of both procaryotic and eukaryotic taxa, whose action is to relieve the cells of multiple, structurally dissimilar, toxic compounds. The possible role of P-gps in defence against the insecticides temephos and diflubenzuron was investigated in the mosquito Aedes caspius (Pallas), also known as Ochlerotatus (Aedes) caspius (Diptera: Culicidae), and the genomic DNA sequences encoding for P-gp transporters were isolated to provide molecular instruments for future research into the expression and characterization of genes codifying for P-gps in this mosquito species.
Mosquito larvae were treated with insecticides alone and in conjunction with a sublethal dose of the P-gp inhibitor verapamil. The inhibition of P-gps reduced the LD₅₀ values of temephos and diflubenzuron by factors of 3.5 and 16.4, respectively, suggesting the potential involvement of P-gps in insecticide defence. Using a polymerase chain reaction (PCR)-based approach, a 481-bp sequence was isolated. The inferred nucleotide sequence shows high homology with the C-terminal sequence of known P-gps. The isolation and characterization of a putative P-gp sequence from Ae. caspius is the first step towards a better molecular understanding of the role played by multidrug transporters in the defence against insecticides in this species. This knowledge may open the way to a novel control strategy based on the inhibition of pest defences. The beneficial consequences of the inhibition of efflux pumps in improving insecticide performance are discussed.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Romeo Bellini

Research topic(s) for pests/diseases/weeds:
pesticide resistance of pest

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Aedes caspius