文献类型： 外文期刊

作者： Tang, Baozhen ¹ ; Dong, Wei ¹ ; Liang, Pei ¹ ; Zhou, Xuguo ³ ; Gao, Xiwu ¹ ;

作者机构： 1.China Agr Univ, Dept Entomol, Beijing 100193, Peoples R China

2.Chinese Acad Sci, Inner Mongolia Prataculture Res Ctr, Hohhot 010031, Peoples R China

3.Univ Kentucky, Dept Entomol, Lexington, KY 40546 USA

关键词： Plutella xylostella;Ecdysone receptor (EcR);Binding affinity;Expression profiling;Ecdysone agonist

期刊名称：BMC MOLECULAR BIOLOGY （ 影响因子：2.946； 五年影响因子：3.192 ）

ISSN： 1471-2199

年卷期： 2012 年 13 卷

页码：

收录情况： SCI

摘要： Background: The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a devastating pest of cruciferous crops worldwide, and has developed resistance to a wide range of insecticides, including diacylhydrazine-based ecdysone agonists, a highly selective group of molt-accelerating biopesticides targeting the ecdysone receptors. Result: In this study, we cloned and characterized the ecdysone receptors from P. xylostella, including the two isoforms of EcR and a USP. Sequence comparison and phylogenetic analysis showed striking conservations among insect ecdysone receptors, especially between P. xylostella and other lepidopterans. The binding affinity of ecdysteroids to in vitro-translated receptor proteins indicated that PxEcRB isoform bound specifically to ponasterone A, and the binding affinity was enhanced by co-incubation with PxUSP (K-d = 3.0 +/- 1.7 nM). In contrast, PxEcRA did not bind to ponasterone A, even in the presence of PxUSP. The expression of PxEcRB were consistently higher than that of PxEcRA across each and every developmental stage, while the pattern of PxUSP expression is more or less ubiquitous. Conclusions: Target site insensitivity, in which the altered binding of insecticides (ecdysone agonists) to their targets (ecdysone receptors) leads to an adaptive response (resistance), is one of the underlying mechanisms of diacylhydrazine resistance. Given the distinct differences at expression level and the ligand-binding capacity, we hypothesis that PxEcRB is the ecdysone receptor that controls the remodeling events during metamorphosis. More importantly, PxEcRB is the potential target site which is modified in the ecdysone agonist-resistant P. xylostella.