Molecular cloning and characterization of the complete acetylcholinesterase gene (Ace1) from the mosquito Aedes aegypti with implications for comparative genome analysis

Abstract

Insensitive acetylcholinesterase (AChE) has been shown to be responsible for resistance to organophosphates and carbamates in a number of arthropod species. Some arthropod genomes contain a single Ace gene, while others including mosquitoes contain two genes, but only one confers insecticide resistance. Here we report the isolation of the full-length cDNA and characterization of the complete genomic DNA sequence for the Ace1 gene in the yellow fever mosquito, Aedes aegypti. The Ace1 homolog in other mosquito species has been associated with insecticide resistance. The full-length cDNA consists of 2,721 bp and contains a 2,109 bp open reading frame that encodes a 702 amino acid protein. The amino acid sequence is highly conserved with that of other mosquitoes, including greater than 90% identity with Culex spp. and about 80% identity with Anopheles gambiae. The genomic DNA sequence includes 138,970 bp and consists of eight exons with seven introns ranging from 59 to 114,350 bp. Exons 2 and 8 show reduced amino acid conservation across mosquito species, while exons 3-7 are highly conserved. The Ace1 introns in Ae. aegypti reflect a high frequency of repetitive sequences that comprise about 45% of the total intron sequence. The Ace1 locus maps to the p-arm of chromosome 3, which corresponds to the orthologous genome regions in Culex spp. and An. gambiae.

RNA INTERFERENCE OF TWO ACETYLCHOLINESTERASE GENES IN Plutella xylostella REVEALS THEIR DIFFERENT FUNCTIONS

“…As the target of organophosphorous (OP) and carbamate pesticides, it has received widely attentions. There are two ace genes in many insects such as Anopheles gambiae (Weill et al, ), Aphis gossypii (Li and Han, ), Schizaphis graminum (Gao et al, ), Culex pipiens (Huchard et al, ), Aedes aegypti (Mori et al, ), Culex tritaeniorhynchus (Nabeshima et al, ), Myzus persicae (Nabeshima et al, ), Rhopalosiphum padi , and Sitobion avenae (Chen and Han, ), Helicoverpa assulta (Lee et al, ), Plutella xylostella (Baek et al, ; Lee et al, ), and Bombyx mori (Chen et al, ). Two ace genes exist in most insects except Cyclorrapha suborder of Diptera (Huchard et al, ).…”

RNA interference of ace1 and ace2 in Chilo suppressalis reveals their different contributions to motor ability and larval growth

“…In 2002, two ace genes were found in Aphis gossypii (Li & Han, 2002) and Anopheles gambiae (Weill et al ., 2002). Since then, two ace genes have been identified in many other insects, such as Culex pipiens (Huchard et al ., 2006), Aedes aegypti (Mori et al ., 2007), Culex tritaeniorhynchus (Nabeshima et al ., 2004), Myzus persicae (Nabeshima et al ., 2003), Rhopalosiphum padi and Sitobion avenae (Chen & Han, 2006) , Helicoverpa assulta (Lee et al ., 2006), Plutella xylostella (Baek et al ., 2005; Lee et al ., 2007) and Bombyx mori (Chen et al ., 2009). It has been suggested that the two ace s in insects originated from duplication before the diversification of arthropods (Labbe et al ., 2007).…”

Cloning and characterization of acetylcholinesterase 1 genes from insecticide-resistant field populations of Liposcelis paeta Pearman (Psocoptera: Liposcelididae)

“…Several studies have reported that both quantitative and qualitative changes in AChE conferred resistance to insecticides (Fournier et al, 1992(Fournier et al, , 1993. In insects, two different ace genes have been found in various species, such as Anopheles gambiae (Weill et al, 2002), Aphis gossypii (Li and Han, 2002), Culex pipiens (Huchard et al, 2006), Aedes aegypti (Mori et al, 2007), Myzus persicae (Nabeshima et al, 2003) and Bombyx mori (Seino et al, 2007). Some studies indicated that ace 1 gene transcripts are much more abundant than ace 2.…”