Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400715, China.
Int J Mol Sci. 2013 Dec 13;14(12):24255-70. doi: 10.3390/ijms141224255.
The citrus red mite, Panonychus citri (McGregor), is a global citrus pest, and has developed severe resistance to several types of acaricides. However, the molecular mechanisms of resistance in this mite remain unknown. In this study, seven full-length cDNAs encoding glutathione S-transferases (GSTs) genes were identified and characterized in P. citri. The effects of pyridaben and fenpropathrin exposure on the expression of these genes were also investigated. Phylogenetic analysis revealed that the seven GSTs genes in P. citri cloned in this study belong to three different cytosolic classes, including four in mu, two in delta and one in zeta. Among these seven GSTs genes, the relative expression level of PcGSTm1 was significantly higher in adult than in the other life stages (egg, larvae and nymph). Compared with the control, the mRNA levels of the seven GST genes did not change significantly following exposure to pyridaben at LC10. However, RT-qPCR results showed that, when exposed to LC10 of fenpropathrin, six GSTs gene (PcGSTm1, PcGSTm3, PcGSTm4, PcGSTd1, PcGSTd2 and PcGSTz1) transcripts increased in a time-dependent manner. This is the first insight into the molecular characteristics of GSTs gene cDNAs in P. citri. The elevated GSTs gene transcripts following exposure to fenpropathrin might be one of the mechanisms involved in detoxification of this acaricide.
柑橘全爪螨，又称柑桔红蜘蛛，是一种全球性的柑橘害虫，对几种杀螨剂产生了严重的抗药性。然而，这种螨虫的抗药性的分子机制尚不清楚。在本研究中，从柑橘全爪螨中鉴定并表征了 7 个编码谷胱甘肽 S-转移酶（GSTs）基因的全长 cDNA。还研究了啶虫脒和甲氰菊酯暴露对这些基因表达的影响。系统进化分析表明，本研究中克隆的柑橘全爪螨的 7 个 GSTs 基因属于三个不同的胞质类，包括 4 个 mu 类、2 个 delta 类和 1 个 zeta 类。在这 7 个 GSTs 基因中，PcGSTm1 在成螨中的相对表达水平明显高于其他生命阶段（卵、幼虫和若螨）。与对照组相比，啶虫脒暴露在 LC10 时，7 个 GST 基因的 mRNA 水平没有明显变化。然而，RT-qPCR 结果表明，当暴露于甲氰菊酯 LC10 时，6 个 GSTs 基因（PcGSTm1、PcGSTm3、PcGSTm4、PcGSTd1、PcGSTd2 和 PcGSTz1）的转录物呈时间依赖性增加。这是首次深入了解柑橘全爪螨 GSTs 基因 cDNA 的分子特征。甲氰菊酯暴露后 GSTs 基因转录物的升高可能是该杀螨剂解毒的机制之一。
