外源dsRNA介导的RNAi对烟草CMV侵染的抑制作用

Inhibitory effect of exogenous dsRNA-mediated RNAi on CMV infection in tobacco

为研究外源dsRNA介导的RNA干扰(RNA interference,RNAi)对烟草黄瓜花叶病毒(cucumber mosaic virus,CMV)侵染的抑制作用,选择与病毒在寄主体内胞间移动和长距离运输密切相关的移动蛋白(Movement protein,MP)基因为靶标,通过克隆CMV MP基因,结合序列分析评估设计dsRNA,以体外合成的方式制备了MP基因中一段490 bp的dsRNA。通过与CMV共接种,结合MP基因表达水平和病毒发病症状,综合评价MP dsRNA对CMV的抑制效果。结果表明,外源喷施的MP dsRNA显著降低了染病烟株中CMV基因的表达水平,有效抑制了病毒的侵染和危害,具有烟草CMV生物防治的应用潜力。

To study the inhibitory effect of exogenous dsRNA-mediated RNAi on tobacco CMV(cucumber mosaic virus)infection,the MP gene encoding movement protein which is closely related to virus movement in the host,was selected as the target gene.By cloning the CMV MP gene,combining with sequence analysis and dsRNA evaluation,a 490 bp dsRNA fragment targeted to MP gene was designed and prepared by in vitro synthesis.After co-inoculation with CMV,the RNAi effect of MP dsRNA was comprehensively evaluated with the expression level of MP gene and the symptoms of virus.It was found that exogenous MP dsRNA applied to tobacco leaves could significantly reduce the expression level of CMV in infected plants,and effectively alleviate the infection and damage of CMV.Therefore,exogenous MP dsRNA can be considered for its potential in biological control of CMV in tobacco.