Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Punjab, Pakistan.
Pakistan Institute of Engineering & Applied Sciences (PIEAS), Nilore, Islamabad, Pakistan.
Insect Mol Biol. 2019 Dec;28(6):785-797. doi: 10.1111/imb.12589. Epub 2019 May 6.
Gut-expressed aphid genes, which may be more easily inhibited by RNA interference (RNAi) constructs, are attractive targets for pest control efforts involving transgenic plants. Here we show that expression of cathepsin L, which encodes a cysteine protease that functions in aphid guts, can be reduced by expression of an RNAi construct in transgenic tobacco. The effectiveness of this approach is demonstrated by up to 80% adult mortality, reduced fecundity, and delayed nymph production of Myzus persicae (green peach aphids) when cathepsin L expression was reduced by plant-mediated RNAi. Consistent with the function of cathepsin L as a gut protease, M. persicae fed on the RNAi plants had a lower protein content in their bodies and excreted more protein and/or free amino acids in their honeydew. Larvae of Coccinella septempunctata (seven-spotted ladybugs) grew more slowly on aphids having reduced cathepsin L expression, suggesting that prey insect nutritive value, and not just direct negative effects of the RNAi construct, needs to be considered when producing transgenic plants for RNAi-mediated pest control.
在涉及转基因植物的害虫防治工作中，肠表达的蚜虫基因可能更容易被 RNA 干扰 (RNAi) 构建体抑制，因此成为有吸引力的目标。在这里，我们表明，通过在转基因烟草中表达 RNAi 构建体，可以降低编码在蚜虫肠道中起作用的半胱氨酸蛋白酶的组织蛋白酶 L 的表达。通过植物介导的 RNAi 降低组织蛋白酶 L 的表达，烟粉虱（桃蚜）的成虫死亡率高达 80%，繁殖力降低，若虫产生延迟，证明了这种方法的有效性。与组织蛋白酶 L 作为肠道蛋白酶的功能一致，在 RNAi 植物上取食的烟粉虱体内的蛋白质含量较低，在蜜露中排泄的蛋白质和/或游离氨基酸更多。具有降低的组织蛋白酶 L 表达的烟粉虱幼虫生长速度较慢，这表明在生产用于 RNAi 介导的害虫防治的转基因植物时，需要考虑猎物昆虫的营养价值，而不仅仅是 RNAi 构建体的直接负面影响。
