The clone of laccase gene and its potential function in cuticular penetration resistance of Culex pipiens pallens to fenvalerate

Developmental characterization, function and regulation of a Laccase2 encoding gene in the honey bee, Apis mellifera (Hymenoptera, Apinae)

“…The activity of this enzyme was studied in the cuticle of dipteran (Yamazaki, 1969; Barret and Andersen, 1981;Barrett, 1987a,b;Binnington and Barrett, 1988;Sugumaran et al, 1992;Charalambidis et al, 1994) and lepidopteran species (Yamazaki, 1972;Thomas et al, 1989), and in some of them the temporal changes in the activity seemed to be linked to cuticle sclerotization. More recently, cDNAs for one or for the two laccase genes (lac1 and lac2) found in insect genomes were characterized in species of Diptera and Lepidoptera (Dittmer et al, 2004;Gorman et al, 2008;Pan et al, 2009;Yatsu and Asano, 2009), and also in two species of Coleoptera (Arakane et al, 2005;Niu et al, 2008). Additionally, the amino acid sequence of laccase2 from the cuticle of Manduca sexta was experimentally determined by expressing and purifying full-length and recombinant forms of the protein (Dittmer et al, 2009), thus confirming identity predicted from the corresponding cDNA sequence (Dittmer et al, 2004).…”

“…Laccase transcripts were also found in eggs of C. pipiens (Pan et al, 2009), suggesting a function in chorion hardening.…”

“…Since then, laccase activity has been studied in other insect species (see review in Andersen, 2005). Only recently, studies have been dealing with laccase characterization at the gene level in insects (Dittmer et al, 2004;Arakane et al, 2005;Niu et al, 2008;Pan et al, 2009;Yatsu and Asano, 2009). …”

Laccase2 is required for cuticular pigmentation in stinkbugs

“…In the Japanese pine sawyer beetle Monochanus alternatus that vectors pinewood nematode and severely damages the pine forest, knockdown of the laccase2 gene expression resulted in mortality of the pest insect (Niu et al, 2008), so did in the red flour beetle T. castaneum known as pest of stored products (Arakane et al, 2005). In the house mosquito Culex pipiens, a fenvalerate-resistant population exhibited drastically higher expression levels of laccase2 gene than control mosquito populations, which might be relevant to lower permeability of the insecticide through thicker cuticle (Pan et al, 2009). The laccase2 gene may provide a novel target for control and management of a wide array of insect pests, either via suppressing the gene expression or via inhibiting the enzymatic activity of the gene product.…”

Insecticide resistance mechanisms associated with different environments in the malaria vector Anopheles gambiae: a case study in Tanzania

“…Resistance to pyrethroids appears to rely mainly on the ‘knock down resistance’ target-site mutations ( kdr ) and metabolic resistance mechanisms, although other mechanisms, such as cuticle alteration have also been evoked [18-20]. Kdr mutations and elevated levels of detoxification enzymes also confer resistance to DDT while carbamate resistance can be conferred by ace1 mutation and detoxification [21-23].…”