Department of Biological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
Insect Biochem Mol Biol. 2009 Nov;39(11):824-32. doi: 10.1016/j.ibmb.2009.09.007. Epub 2009 Oct 6.
A serious shortcoming of many insecticides is that they can kill non-target species. To address this issue, we harnessed the sequence specificity of RNA interference (RNAi) to design orally-delivered double-stranded (ds) RNAs that selectively killed target species. Fruit flies (Drosophila melanogaster), flour beetles (Tribolium castaneum), pea aphids (Acyrthosiphon pisum), and tobacco hornworms (Manduca sexta) were selectively killed when fed species-specific dsRNA targeting vATPase transcripts. We also demonstrate that even closely related species can be selectively killed by feeding on dsRNAs that target the more variable regions of genes, such as the 3' untranslated regions (UTRs): four species of the genus Drosophila were selectively killed by feeding on short (<40 nt) dsRNAs that targeted the 3' UTR of the gamma-tubulin gene. For the aphid nymphs and beetle and moth larvae, dsRNA could simply be dissolved into their diets, but to induce RNAi in the drosophilid species, the dsRNAs needed to be encapsulated in liposomes to help facilitate uptake of the dsRNA. This is the first demonstration of RNAi following ingestion of dsRNA in all of the species tested, and the method offers promise of both higher throughput RNAi screens and the development of a new generation of species-specific insecticides.
许多杀虫剂的一个严重缺点是它们会杀死非目标物种。为了解决这个问题，我们利用 RNA 干扰 (RNAi) 的序列特异性来设计可口服的双链 (ds) RNA，这些 RNA 可以选择性地杀死目标物种。当喂食针对 vATPase 转录本的特异性 dsRNA 时，果蝇（Drosophila melanogaster）、粉斑螟（Tribolium castaneum）、豌豆蚜（Acyrthosiphon pisum）和烟草天蛾（Manduca sexta）会被选择性杀死。我们还证明，即使是密切相关的物种也可以通过喂食针对基因更可变区域（如 3'非翻译区（UTR））的 dsRNA 来选择性杀死：喂食针对γ-微管蛋白基因 3'UTR 的短 (<40nt) dsRNA 可选择性杀死四种果蝇物种。对于蚜虫若虫和甲虫及蛾幼虫，dsRNA 可以简单地溶解在它们的饮食中，但为了在果蝇物种中诱导 RNAi，dsRNA 需要封装在脂质体中以帮助促进 dsRNA 的摄取。这是在所有测试物种中首次证明口服 dsRNA 后会引发 RNAi，该方法有望实现更高通量的 RNAi 筛选和新一代的特异性杀虫剂的开发。
