Abstract Whitefly (Bemicia tabaci) is an insect pest that causes severe losses in economically important crops by sucking the plant sap and transmitting plant viruses. We used the promising new approach of plant-mediated artificial miRNA (amiRNA) expression against three essential genes of whitefly. The Arabidopsis thaliana miR159 precursor was modified and engineered to express artificial miRNAs (amiRNAs) targeting three vital genes of whitefly, sex lethal (Sxl) protein, acetylcholinesterase (AChE) and orcokinin (Orc). The amiRNAWF construct was transformed into the Nicotiana tabacum plants. Whiteflies were infested in separate cages on both control and transgenic plants. After four weeks of infestation, the nymphs were counted and real time quantitative PCR (RT-qPCR) was performed to assess the relative expression of whitefly genes. The transgenic N. tabacum plants showed resistance against whitefly and the number of whiteflies in the next generation were substantially reduced on transgenic plants compared to control plants. Abnormal egg hatching and poor development was observed and only a small number of whitefly nymphs matured to adults. RT-qPCR results indicated that the expression of target genes (Sxl, AChE and Orc) in the nymphs was considerably down-regulated in whiteflies reared on transgenic plants. The amiRNA mediated resistance against whitefly in transgenic plants may pave the way for engineering resistance against whitefly in cotton plants.

中文翻译：

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人工微 RNA (amiRNA) 介导的针对三个基因的粉虱（Bemisia tabaci）抗性

摘要 粉虱（Bemicia tabaci）是一种害虫，通过吸食植物汁液并传播植物病毒，对重要经济作物造成严重损失。我们使用了植物介导的人工 miRNA (amiRNA) 表达的有前途的新方法来对抗粉虱的三个基本基因。拟南芥 miR159 前体经过修饰和工程化，以表达针对粉虱、性致死 (Sxl) 蛋白、乙酰胆碱酯酶 (AChE) 和 orcokinin (Orc) 三个重要基因的人工 miRNA (amiRNA)。amiRNAWF 构建体被转化到烟草植物中。粉虱在对照植物和转基因植物的单独笼子中侵染。感染 4 周后，对若虫进行计数，并进行实时定量 PCR (RT-qPCR) 以评估粉虱基因的相对表达。转基因烟草植物表现出对粉虱的抗性，与对照植物相比，转基因植物的下一代粉虱数量显着减少。观察到异常卵孵化和发育不良，只有少数粉虱若虫成熟为成虫。RT-qPCR 结果表明，在转基因植物上饲养的粉虱中，若虫中靶基因（Sxl、AChE 和 Orc）的表达显着下调。amiRNA介导的转基因植物对粉虱的抗性可能为棉花植物对粉虱的工程抗性铺平道路。观察到卵孵化异常和发育不良，只有少数粉虱若虫成熟为成虫。RT-qPCR 结果表明，在转基因植物上饲养的粉虱中，若虫中靶基因（Sxl、AChE 和 Orc）的表达显着下调。amiRNA介导的转基因植物对粉虱的抗性可能为棉花植物对粉虱的工程抗性铺平道路。观察到卵孵化异常和发育不良，只有少数粉虱若虫成熟为成虫。RT-qPCR 结果表明，在转基因植物上饲养的粉虱中，若虫中靶基因（Sxl、AChE 和 Orc）的表达显着下调。amiRNA介导的转基因植物对粉虱的抗性可能为棉花植物对粉虱的工程抗性铺平道路。