title: Gene expression analysis and enzyme assay reveal a potential role of the carboxylesterase gene CpCE-1 from Cydia pomonella in detoxification of insecticides.
abstract: Carboxylesterases (CarEs) are responsible for metabolism of xenobiotics including insecticides in insects. Understanding the expression patterns of a such detoxifying gene and effect of insecticides on its enzyme activity are important to clarify the function of this gene relevant to insecticides-detoxifying process, but little information is available in the codling moth Cydia pomonella (L.). In this study, we investigated the expression profiles of CarE gene CpCE-1 at different developmental stages and in different tissues of C. pomonella, as well as the larvae exposed to chlorpyrifos-ethyl and lambda-cyhalothrin by using absolute real-time quantitative PCR (absolute RT-qPCR). Results indicated that CpCE-1 expression was significantly altered during C. pomonella development stages, and this expression differed between sexes, with a higher transcript in females than males. Meanwhile, CpCE-1 is overexpressed in cuticle, midgut and head than silk gland, fat body and Malpighian tubules. Exposure of third instar larvae to a non-lethal dosage of chlorpyrifos-ethyl and lambda-cyhalothrin resulted in induction of CpCE-1 transcript. The total carboxylesterase enzyme activity was inhibited by chlorpyrifos-ethyl in vivo; in contrast, the activity of Escherichia coli produced recombinant CpCE-1 was significantly inhibited by both lambda-cyhalothrin and chlorpyrifos-ethyl in vitro. These results suggested that CpCE-1 in C. pomonella is potentially involved in the development and in detoxification of chlorpyrifos-ethyl and lambda-cyhalothrin.
authors.affiliation: Key Laboratory of Economical and Applied Entomology of Liaoning Province, College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, Liaoning, China. Electronic address: sling233@hotmail.com.
authors.forename: Xue-Qing
authors.initials: XQ
authors.lastname: Yang
mesh_terms: D000818:Animals; D043182:Carboxylesterase / Q000235:genetics*; D020869:Gene Expression Profiling; D008658:Inactivation, Metabolic; D007306:Insecticides / Q000378:metabolism / Q000633:toxicity*; D007915:Lepidoptera / Q000235:genetics*
chemical_list: D007306:Insecticides; D043182:Carboxylesterase
keywords: Absolute RT-qPCR; Carboxylesterase; Cydia pomonella; Detoxification; Inhibition