Transcription analysis of differentially expressed genes in insecticide-resistant Aedes aegypti mosquitoes after deltamethrin exposure

Abstract

Aedes aegypti mosquitoes are resistant to various insecticides, including pyrethroids, throughout Thailand. We previously reported that Ae. aegypti from Mae Wong district, Nakhon Sawan Province in north-central Thailand, were resistant to insecticides, including pyrethroids (deltamethrin and permethrin), organophosphates and carbamates, and that high levels of detoxification enzymes were present. In the present study we used the method of suppression by subtractive hybridization to determine differential expression of genes in Mae Wong Ae. aegypti that survived the exposure to increasing doses (~1.5 -2 x 10 -5 M) of deltamethrin beyond the diagnostic dose compared to unexposed mosquitoes. Screening of 350 cDNA clones from the suppression subtractive library by cDNA array hybridization revealed that 58 clones were over-expressed in the mosquito that survived high dose deltamethrin. The over-expressed cDNA insert sequences corresponded to 11 functional genes, five hypothetical protein genes, and five sequences of unknown function that could be located on the supercontig of the Ae. aegypti genome. The functional genes are those coding for cuticular proteins, muscle proteins, proteins related to controlling the release of synaptic vesicles, and other genes such as heat shock protein and small subunit ribosomal RNA. Over-expression of tomosyn and myosin light chain kinase genes was verified using a semiquantitative reverse transcription-polymerase chain reaction (RT-PCR), confirming their increased expression in response to deltamethrin exposure in insecticide-resistant Ae. aegypti. Journal of Vector Ecology 35 (1): 197-203. 2010.

Preliminary characterization of putative structural cuticular proteins in the malaria vector Anopheles sinensis

“…Knowledge of the molecular mechanisms contributing to insecticide resistance is a basic requirement for overcoming this challenge. Importantly, the cuticle can impede the absorbance of insecticides, and several CPs are differentially expressed in insecticide resistant and susceptible strains in Culex pipiens pallens , Aedes aegypti , Anopheles gambiae and Anopheles stephensi . Recently, experimental evidence in C. pipiens pallens revealed that CPs can alter the sensitivity to deltamethrin.…”

Genome-Wide Identification and Transcriptome-Based Expression Profile of Cuticular Protein Genes in Antheraea pernyi

“…Structural cuticular proteins (CPs) are the primary component of insect cuticle [ 1 , 2 ], and can form the Bouligand model to stabilize the complex structure of the cuticle in maintaining the elasticity and other physical properties of insects [ 3 ]. Evidence from Culex pipiens pallens L. [ 4 , 5 ], Aedes aegypti L. [ 6 ] and Bactrocera dorsalis Hendel [ 7 ] have indicated that some CPs are involved in the response to pesticides and arid and extreme temperature conditions. However, CPs vary greatly in number, sequence and structure within and between species [ 7 , 8 , 9 , 10 ].…”

Comparative Transcriptomic Analysis of Insecticide-Resistant Aedes aegypti from Puerto Rico Reveals Insecticide-Specific Patterns of Gene Expression

“…Both target site insensitivity and metabolic resistance have been identified as important mechanisms of insecticide resistance in Ae. aegypti, and several previous studies have investigated the specific genes involved in metabolic detoxification of insecticides in this mosquito species [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. This study aimed to disentangle the transcriptional basis of resistance to multiple insecticides in Ae.…”