Nanoparticle mediated RNAi in insects: A novel feeding assay based method for controlling insect pests

Abstract

Post transcriptional gene silencing through RNA interference (RNAi) technology has opened a new avenue to control insects. Due to several physicochemical properties the repression efficiency of gene expression by double stranded RNA (dsRNA) in insect cells is not very high. Nowadays nanoparticle (NP) mediated delivery of dsRNA is gradually gaining popularity to improve its gene silencing efficiency in insects. NP mediated delivery method will not only increase the stability of dsRNA, but also will facilitate its delivery and endosomal release for efficient gene silencing. Additionally, this delivery method is target specific, so will be safe to other organisms in the ecosystem. This technology has the potential to become a more sustainable and eco-friendly pest control method. The main challenge in widespread use of RNAi technology for controlling insect pests is the development of effective and reliable dsRNA delivery methods. Microinjection is not a viable method for triggering RNAi in insects at bulk scale, specifically if we think of controlling insect pests in agricultural set up. Here, we have developed a feeding assay based method to deliver dsRNA, tagged with nanocarriers, to knock down insect genes. This delivery approache has the potential to increase the retention time of the dsRNAs in the circulatory system by reducing the rate of clearance, protect the dsRNAs from gut nucleases, ensure stability of dsRNA in the lumen of the alimentary canal, facilitate targeting and uptake of the dsRNAs into the target cells and promote trafficking in the cytoplasm and uptake into RNA-induced silencing complex. This technology has the potential to become a more sustainable and eco-friendly pest control method and can also be utilized to control other insect vectors.