Abstract
RNA interference (RNAi) is useful for controlling pests of agriculturally important crops. The soybean pod borer (SPB) is the most important soybean pest in Northeastern Asia. In an earlier study, we confirmed that the SPB could be controlled via transgenic plant-mediated RNAi. Here, the SPB transcriptome was sequenced to identify RNAi-related genes, and also to establish an RNAi-of-RNAi assay system for evaluating genes involved in the SPB systemic RNAi response. The core RNAi genes, as well as genes potentially involved in double-stranded RNA (dsRNA) uptake were identified based on SPB transcriptome sequences. A phylogenetic analysis and the characterization of these core components as well as dsRNA uptake related genes revealed that they contain conserved domains essential for the RNAi pathway. The results of the RNAi-of-RNAi assay involving Laccase 2 (a critical cuticle pigmentation gene) as a marker showed that genes encoding the sid-like (Sil1), scavenger receptor class C (Src), and scavenger receptor class B (Srb3 and Srb4) proteins of the endocytic pathway were required for SPB cellular uptake of dsRNA. The SPB response was inferred to contain three functional small RNA pathways (i.e., miRNA, siRNA, and piRNA pathways). Additionally, the SPB systemic RNA response may rely on systemic RNA interference deficient transmembrane channel-mediated and receptor-mediated endocytic pathways. The results presented herein may be useful for developing RNAi-mediated methods to control SPB infestations in soybean.
Highlights
RNA interference (RNAi) is an evolutionarily conserved mechanism that refers to a set of molecular processes in which small RNA molecules exert a silencing effect on complementary mRNAs (Miyata et al, 2014; Ganbaatar et al, 2017).The RNAi-based technology has recently been exploited to control insect pests of agriculturally important crops (Mao and Zeng, 2014)
We focused on RNAi, our transcriptome data enabled the rapid discovery of diverse soybean pod borer (SPB) candidate genes
All core RNAi machinery-related genes were detected in the SPB transcriptome, often encoding full-length open reading frames (Table S5), implying that the SPB larvae contain functional miRNA, small interfering RNA (siRNA), and piwi-interacting RNA (piRNA) pathways
Summary
RNA interference (RNAi) is an evolutionarily conserved mechanism that refers to a set of molecular processes in which small RNA (sRNA) molecules exert a silencing effect on complementary mRNAs (Miyata et al, 2014; Ganbaatar et al, 2017).The RNAi-based technology has recently been exploited to control insect pests of agriculturally important crops (Mao and Zeng, 2014). The application of RNAi technology to control pests is based on the RNA Interference-Related Genes introduction of exogenous double-stranded RNA (dsRNA) into insects to silence the target genes, thereby activating the siRNA pathway (Joga et al, 2016). The dsRNA-binding motif protein, R2D2, ensures siRNA is properly loaded into the RNA-induced silencing complex (RISC) (Nishida et al, 2013; Swevers et al, 2013). Using siRNA as a guide, the RISC locates the target mRNA, which is cleaved by Argonaute to downregulate protein expression (Azlan et al, 2016)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
