Expression data from KOBU-induced Arabidopsis

Plant viruses induce various disease symptoms, but their underlying mechanisms are poorly understood. Kobu-sho is a disease in gentian that show gall formation with ectopic development of lignified cells and vascular tissues such as xylem. Recently, we identified a novel unusual RNA virus, gentian Kobu-sho-associated virus (GKaV) from Kobu-sho-affected gentian. Here, we show that a gene fragment of GKaV, Kobu-sho-inducing factor (KOBU), induces gall formation accompanied with ectopic development of lignified cells and xylem-like tissue in Nicotiana benthamiana. We identify KOBU by screening using potato virus X vector in N. benthamiana, and confirm that transgenic gentian expressing KOBU causes tumorous symptom. Transgenic Arabidopsis thaliana expressing KOBU activates signaling pathways regulating xylem development. KOBU protein forms granules and plate-like structures and co-localizes with mRNA splicing factors within nucleus. Our findings provide novel insights into not only virus disease development but also vascular development in plant. Arabidopsis that express KOBU by DEX dependent manner were selected at successive induced time for RNA extraction and hybridization on Affymetrix microarrays. We prepared samples afther the treatment with DEX for 4hr, 8hr, 12hr, 1day, 2day, 3day, 5day, and 7day.