树皮甲虫依靠解毒酶来抵抗寄主树的防御性萜类化合物。昆虫细胞色素P450(CYPs)在农药和植物化感物质的解毒中起着关键作用。CYP6家族是昆虫纲特有的,其生化功能基本上与外源性物质的代谢有关。在这项研究中,我们对来自白松甲虫的两个CYP6基因的全长cDNA进行了测序和表征,Dendroctonusarmandi.时空表达谱显示,CYP6CR2和CYP6DE5在D.armandi幼虫和成虫阶段的表达高于其他发育阶段。这两个基因主要在大脑中表达,中肠,脂肪的身体,马氏小管或血淋巴。取食华山松韧皮部并暴露于六种刺激后,CYP6CR2和CYP6DE5的表达显着诱导[(±)-α-pine烯,(-)-α-品烯,(-)-β-品烯,(+)-3-carene,(±)-柠檬烯和松节油]。重要的是,分别沉默CYP6CR2和CYP6DE5可以提高敏感性,导致P450的活性显着降低,导致萜类化合物治疗后成人死亡率显着增加。本研究的综合结果表明,在寄主选择和定殖过程中,CYPs的功能主要是水解宿主的化学防御和降解气味分子。这些发现可能有助于开发新的治疗方法来控制这种重要的害虫。
Bark beetles rely on detoxifying enzymes to resist the defensive terpenoids of the host tree. Insect cytochrome P450 (CYPs) plays a key role in the detoxification of pesticides and plant allelochemicals. CYP6 family is unique to Insecta, and its biochemical function is basically related to the metabolism of exogenous substances. In this study, we sequenced and characterized the full-length cDNAs of two CYP6 genes from Chinese white pine beetle, Dendroctonus armandi. Spatiotemporal expression profiling revealed that the expression of CYP6CR2 and CYP6DE5 was higher in larval and adult stages of D. armandi than that in other developmental stages, and that two genes predominantly expressed in brain, midgut, fat body, Malpighian tubules or hemolymph. The expression of CYP6CR2 and CYP6DE5 was significantly induced after feeding on the phloem of Pinus armandii and exposure to six stimuli [(±)- α -pinene, (-)-α-pinene, (-)-β-pinene, (+)-3-carene, (±)-limonene and turpentine]. Importantly, silencing CYP6CR2 and CYP6DE5 separately could increase the sensitivity, led to a significant reduction of the activity of P450, resulting a significant increase in adult mortality after treatment with terpenoids. The comprehensive results of this study showed that in the process of host selection and colonization, the functions of CYPs were mainly to hydrolyze the chemical defense of the host and degrade odor molecules. These findings may help to develop new treatments to control this important pest.