Title : High chlorpyrifos resistance in Culex pipiens mosquitoes: strong synergy between resistance genes - Alout_2016_Heredity.(Edinb)_116_224 |
Author(s) : Alout H , Labbe P , Berthomieu A , Makoundou P , Fort P , Pasteur N , Weill M |
Ref : Heredity (Edinb) , 116 :224 , 2016 |
Abstract :
We investigated the genetic determinism of high chlorpyrifos resistance (HCR), a phenotype first described in 1999 in Culex pipiens mosquitoes surviving chlorpyrifos doses 1 mg l(-1) and more recently found in field samples from Tunisia, Israel or Indian Ocean islands. Through chlorpyrifos selection, we selected several HCR strains that displayed over 10 000-fold resistance. All strains were homozygous for resistant alleles at two main loci: the ace-1 gene, with the resistant ace-1(R) allele expressing the insensitive G119S acetylcholinesterase, and a resistant allele of an unknown gene (named T) linked to the sex and ace-2 genes. We constructed a strain carrying only the T-resistant allele and studied its resistance characteristics. By crossing this strain with strains harboring different alleles at the ace-1 locus, we showed that the resistant ace-1(R) and the T alleles act in strong synergy, as they elicited a resistance 100 times higher than expected from a simple multiplicative effect. This effect was specific to chlorpyrifos and parathion and was not affected by synergists. We also examined how HCR was expressed in strains carrying other ace-1-resistant alleles, such as ace-1(V) or the duplicated ace-1(D) allele, currently spreading worldwide. We identified two major parameters that influenced the level of resistance: the number and the nature of the ace-1-resistant alleles and the number of T alleles. Our data fit a model that predicts that the T allele acts by decreasing chlorpyrifos concentration in the compartment targeted in insects. |
PubMedSearch : Alout_2016_Heredity.(Edinb)_116_224 |
PubMedID: 26463842 |
Alout H, Labbe P, Berthomieu A, Makoundou P, Fort P, Pasteur N, Weill M (2016)
High chlorpyrifos resistance in Culex pipiens mosquitoes: strong synergy between resistance genes
Heredity (Edinb)
116 :224
Alout H, Labbe P, Berthomieu A, Makoundou P, Fort P, Pasteur N, Weill M (2016)
Heredity (Edinb)
116 :224