Project description:Verticillium wilt caused by the soil-borne fungus Verticillium dahliae is a common, devastating plant vascular disease notorious for causing economic losses. Despite considerable research on plant resistance genes, there has been little progress in modeling the effects of this fungus owing to its complicated pathogenesis. Here, we analyzed the transcriptional and metabolic responses of Arabidopsis thaliana to V. dahliae inoculation by Illumina-based RNA sequencing (RNA-seq) and nuclear magnetic resonance (NMR) spectroscopy. We identified 13,916 differentially expressed genes (DEGs) in infected compared with mock-treated plants. Gene ontology analysis yielded 11,055 annotated DEGs, including 2,308 for response to stress and 2,234 for response to abiotic or biotic stimulus. Pathway classification revealed involvement of the metabolic, biosynthesis of secondary metabolites, plant-pathogen interaction, and plant hormone signal transduction pathways. In addition, 401 transcription factors, mainly in the MYB, bHLH, AP2-EREBP, NAC, and WRKY families, were up- or downregulated. NMR analysis found decreased tyrosine, asparagine, glutamate, glutamine, and arginine and increased alanine and threonine levels following inoculation, along with a significant increase in the glucosinolate sinigrin and a decrease in the flavonoid quercetin glycoside. Our data reveal corresponding changes in the global transcriptomic and metabolic profiles that provide insights into the complex gene-regulatory networks mediating the plant's response to V. dahliae infection.
Project description:Small RNAs (sRNAs, including small interfering RNAs [siRNAs] and micro RNAs [miRNAs]) are key mediators of RNA silencing (or RNA interference), which play important roles in plant development and response to biotic and abiotic stimulation. Verticillium wilt is a plant vascular disease caused by the soil-borne fungal pathogens, such as Verticillium dahliae. We previously reported that V. dahliae infection increased two plant endogenous miRNAs that were exported to fungal cell to silence virulence genes. To investigate plant sRNAs in genome-wide response to V. dahliae infection, in this study, we constructed two sRNA libraries from Arabidopsis roots with and without V. dahliae infection, respectively. In total, 31 conserved miRNAs were found to be differentially expressed during the early stage of infection with V. dahliae using sRNA sequencing. Among these, the expression levels of miR160, miR164, miR166, miR167, miR390 and miR156h were confirmed by northern blot. Reverse transcription quantitative real time polymerase chain reaction results showed that the induction of miRNAs (miR160, miR164, miR166 and miR167) upon V. dahliae infection downregulated the expression of their targeted genes (ARF10, NAC1, PHV and ARF6), respectively. In addition, we identified specific phased siRNAs generated from distinct regions of two libraries. Profiling of these miRNAs and sRNAs lay the foundation for further understanding and utilising the host-induced gene silencing strategy to control plant vascular pathogens.