Comparative Transcriptome Analysis of Rice stripe virus-viruliferous and Non-viruliferous Laodelphax striatellus

Abstract

Rice stripe virus (RSV) is one of the serious plant pathogenic viruses for rice transmitted by small brown planthopper, SBPH, Laodalphax striatellus. So far, the studies have been mainly focused on the interaction between the host plant and the virus. In this study, for better comprehension of the interactions among Rice stripe virus, rice and small brown planthopper, the transcriptomes of the RSV-viruliferous (RVLS) and non-viruliferous L. striatellus (NVLS) were comparatively analyzed. For this, NVLS were collected from non-infected rice fields were fed with RSV-infected rice for 5 days. With the RNAs extracted from the RVLS and the NVLS, we conducted Illumina RNA sequencing (Hiseq 2000) and as a result two transcriptome databases were constructed from the each sample, respectively. The transcriptome of RVLS and NVLS were compared to figure out how the gene expression of the insects was affected by Rice Stripe Virus. The RSV-dependently regulated genes analyzed from this study may have important functions in the transmission and replication of RSV. RNA interference (RNAi) is an universal gene-knockdown mechanism in eukaryotic organisms which includes insects, and has been considered as an alternative strategy to control insect pests. Hence, we applied this technique to interfere the translation of target RNA genes to knockdown the virus gene on RVLS. Three out of seven RSV genes, RdRp, NS3, and NCP were used as target genes and each dsRNA targeting the viral genes were delivered to the insects indirectly through the rice leaves by irrigation. As a result, not only the relative expression level of target genes decreased but also those of non-target genes and the replication of RSV genome as well. In summary, leaf-mediated dsRNA feeding methods would be useful in the knockdown of target genes on piercing-sucking insects. The genes used in this experiment can be utilized for the development of pest-resistant transgenic plants based on RNAi.