CYP6CM1基因RNA干扰载体的构建及转基因烟草对烟粉虱抗药性的影响

Expression of a CYP6CM1-RNAi cassette in transgenic tobacco and its effect on insecticide resistance of Bemisia tabaci

烟粉虱的抗药性与体内细胞色素P450单加氧酶基因的过量表达有关。根据Q型烟粉虱一个P450基因(CYP6CM1基因)的特异区域构建RNAi载体,通过农杆菌介导法转化烟草,PCR检测获得6个独立转基因株系;以非转基因烟草和T1代转基因烟草饲喂烟粉虱5 d后,荧光定量PCR结果显示取食转基因烟草的烟粉虱体内CYP6CM1基因相对表达量仅为取食非转基因烟草烟粉虱的13%～27%,表明CYP6CM1基因RNAi表达框架可以干扰烟粉虱CYP6CM1基因的表达。

Bemisia tabaci is a worldwide pest and presents high level insecticide resistance. The pesticide resistance has brought great challenge on controlling. The mechanism of Bemisia tabaci resistance to insecticide is relative to the en-hanced detoxification by cytochrome P450 monooxygenases. A RNAi cassette targetting a P450 gene （ CYP6CM1 ） of Bemisia tabaci biotype Q was integrated into tobacco genome through Agrobacterium transformation. Six independent To lines were re-generated and confirmed by PCR, and individuals of TI lines were subjected to Bemisia tabaci. After 5 d feeding, qRT-PCR （ quantitative real-time polymerase chain reaction） result showed that the expression level of CYP6CM1 gene in Bemisia tabaci was only 13%-27% of the control （fed with non-transgenic tobacco）, which suggested that the CYP6CM1-RNAi cassette ex-pressed in transgenic tobacco was effective to decrease the expression of insecticide resistant P450 gene in Bemisia tabaci.