Project description:Plant viruses rely on both host plant and vectors for a successful infection. This study investigated the global transcriptomic changes in Arabidopsis thaliana that were simultaneously exposed to both a plant virus (turnip yellows virus, polerovirus genus and Solemoviridae family) and its aphid vector (Myzus persicae). Some of these modifications in gene expression may promote in a timely manner viral transmission and dispersion.
Project description:In plants and some animal lineages, RNA silencing is an efficient and adaptable defense mechanism against viruses. To counter it, viruses encode suppressor proteins that interfere with RNA silencing. Phloem-restricted viruses are spreading at an alarming rate and cause substantial reduction of crop yield, but how they interact with their hosts at the molecular level is still insufficiently understood. Here, we investigate the antiviral response against phloem-restricted turnip yellows virus (TuYV) in the model plant Arabidopsis thaliana. Using a combination of genetics, deep sequencing, and mechanical vasculature enrichment, we show that the main axis of silencing active against TuYV involves 22-nt vsiRNA production by DCL2, and their preferential loading into AGO1. Moreover, we identify vascular secondary siRNA produced from plant transcripts and initiated by DCL2-processed AGO1-loaded vsiRNA Unexpectedly, and despite the viral encoded VSR P0 previously shown to mediate degradation of AGO proteins, vascular AGO1 undergoes specific post-translational stabilization during TuYV infection. Collectively, our work uncovers the complexity of antiviral RNA silencing against phloem-restricted TuYV and prompts a re-assessment of the role of its suppressor of silencing P0 during genuine infection.
Project description:The western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte) is an important pest of corn (Zea mays) in the US. Annual crop rotation between corn and soybean (Glycine max) disrupts the corn-dependent WCR lifecycle and was widely adopted to manage WCR. However, this strategy selected for a rotation-resistant (RR) variant with reduced ovipositional fidelity to cornfields. Previous studies indicated that RR-WCR adults exhibit greater tolerance of soybean tissue diet, different gut physiology, and host-microbe interactions compared to wild-types (WT). To identify genetic mechanisms underlying these phenotypic changes, a de novo assembly of the WCR adult gut transcriptome was constructed and used for RNA-sequencing analyses on RNA libraries from different WCR phenotypes (RR and WT) fed with corn or soybean diets. Differential gene expression analyses and network-based methods were used to identify gene modules transcriptionally correlated with the RR phenotype. Gene ontology enrichment analyses on these modules were then conducted to understand their potential functions and biological importance. Differential gene expression analyses on RNA libraries from adult guts of different WCR phenotypes (rotation-resistant and wild-type) fed with corn or soybean diets
Project description:Transcriptome sequencing from Nicotiana benthamiana leaves non-infected and infected with Turnip mosaic virus at 6 days post inoculation.
