Jekayinoluwa Temitope, Tripathi Jaindra Nath, Dugdale Benjamin, Obiero George, Muge Edward, Dale James, Tripathi Leena
International Institute of Tropical Agriculture, Biosciences, P.O. Box 30709, Nairobi 00100, Kenya.
Center for Biotechnology and Bioinformatics, University of Nairobi, 30197, Nairobi 00100, Kenya.
Plants (Basel). 2021 Mar 24;10(4):613. doi: 10.3390/plants10040613.
The banana aphid, , is the sole insect vector of banana bunchy top virus (BBTV), the causal agent of banana bunchy top disease. The aphid acquires and transmits BBTV while feeding on infected banana plants. RNA interference (RNAi) enables the generation of pest and disease-resistant crops; however, its effectiveness relies on the identification of pivotal gene sequences to target and silence. Acetylcholinesterase (AChE) is an essential enzyme responsible for the hydrolytic metabolism of the neurotransmitter acetylcholine in animals. In this study, the gene of the banana aphid was targeted for silencing by RNAi through transgenic expression of dsRNA in banana and plantain plants. The efficacy of dsRNA was first assessed using an artificial feeding assay. In vitro aphid feeding on a diet containing 7.5% sucrose, and sulfate complexes of trace metals supported aphid growth and reproduction. When dsRNA was included in the diet, a dose of 500 ng/μL was lethal to the aphids. Transgenic banana cv. Cavendish Williams and plantain cvs. Gonja Manjaya and Orishele expressing dsRNA were regenerated and assessed for transgene integration and copy number. When aphids were maintained on elite transgenic events, there was a 67.8%, 46.7%, and 75.6% reduction in aphid populations growing on Cavendish Williams, Gonja Manjaya, and Orishele cultivars, respectively, compared to those raised on nontransgenic control plants. These results suggest that RNAi targeting an essential aphid gene could be a useful means of reducing both aphid infestation and potentially the spread of the disease they transmit.
香蕉蚜（ ）是香蕉束顶病毒（BBTV）的唯一昆虫传播媒介，而BBTV是香蕉束顶病的病原体。这种蚜虫在取食受感染的香蕉植株时获取并传播BBTV。RNA干扰（RNAi）能够培育出抗病虫害的作物；然而，其有效性依赖于识别关键基因序列以进行靶向和沉默。乙酰胆碱酯酶（AChE）是动物体内负责神经递质乙酰胆碱水解代谢的一种关键酶。在本研究中，通过在香蕉和大蕉植株中进行dsRNA的转基因表达，利用RNAi靶向沉默香蕉蚜的 基因。首先通过人工喂食试验评估dsRNA的效果。在体外，蚜虫取食含有7.5%蔗糖以及微量金属硫酸盐复合物的食物，这有助于蚜虫的生长和繁殖。当食物中加入dsRNA时，500 ng/μL的剂量对蚜虫具有致死性。再生出了表达dsRNA的转基因香蕉品种卡文迪什威廉姆斯以及大蕉品种贡贾曼贾亚和奥里舍勒，并对转基因整合和拷贝数进行了评估。当蚜虫以优良转基因事件植株为食时，与以非转基因对照植株为食的蚜虫相比，在卡文迪什威廉姆斯、贡贾曼贾亚和奥里舍勒品种上生长的蚜虫种群数量分别减少了67.8%、46.7%和75.6%。这些结果表明，靶向蚜虫关键基因的RNAi可能是减少蚜虫侵扰以及潜在减少其所传播疾病扩散的一种有效手段。
