title: Over-transcription of genes in a parathion-resistant strain of mosquito Culex pipiens quinquefasciatus.
abstract: Insecticide resistance is an evolutionary adaptation that develops quite quickly in mosquitoes because of the high selection pressure of chemical insecticides, rapid generation time and large population size. Identification of genes associated with insecticide resistance is fundamental to understand the complex processes responsible for resistance. We compared the gene transcriptional profiles of parathion-resistant and -susceptible Culex pipiens quinquefasciatus using a combination of suppression subtractive hybridization and complementary DNA (cDNA) microarray techniques. A total of 278 colonies were selected from the resistant-susceptible mosquito subtractive library, 38 of which showed more than two fold stronger immunoblotting signals in the resistant strain than in the susceptible strain using cDNA microarray selection. The sequencing results showed that the 38 colonies can be matched to 12 genes of C. p. quinquefasciatus. Eight genes were confirmed to be overexpressed by more than two fold in the resistant strain. These genes encode chymotrypsin-1, theta glutathione S-transferase, lipase 3, larval serum protein 1 β chain, cytochrome b, mitochondrial ribosomal large subunit, 28S rRNA, and a protein with unknown function. This study serves as a preliminary attempt to identify new genes associated with organophosphate resistance in this mosquito species and provides insights into the complicated physiological phenomenon of insecticide resistance.
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing; State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Si-Lu
authors.initials: SL
authors.lastname: Liu
authors.forename: Yang-Yang
authors.initials: YY
authors.lastname: Liu
authors.forename: Chuan-Ling
authors.initials: CL
authors.lastname: Qiao
authors.forename: Shao-Liang
authors.initials: SL
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Cui
mesh_terms: D000818:Animals; D001483:Base Sequence; D003465:Culex / Q000235:genetics*; D018076:DNA, Complementary; D020869:Gene Expression Profiling; D007305:Insecticide Resistance / Q000235:genetics*; D007306:Insecticides / Q000494:pharmacology; D008969:Molecular Sequence Data; D010278:Parathion / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D007306:Insecticides; D010278:Parathion
keywords: cDNA microarray; chymotrypsin; gene up-regulation; insecticide resistance; suppression subtractive hybridization; theta glutathione S-transferase