Time-resolved combined analysis of transcriptome and proteome of the pathogenicity-activated plant pathogen Xanthomonas oryzae pv. oryzae

Xanthomonas oryzae pv. oryzae (Xoo) is a rice pathogen causing bacterial blight, which outbreaks in most rice cultivating countries and reduces yield up to 50% due to no effective pesticide. Urgent responses of Xoo upon the initial contacts with rice at infection site are essential for pathogenesis. We studied the time-resolved gene expression of both transcriptome and proteome in the pathogenicity-activated Xoo cells with an in vitro assay system. Genes related to cell mobility, inorganic ion transport and effectors are early response genes to help Xoo cells invade into damaged rice leaf tissues, obtain rare cofactors, and evade rice immune responses. Although the time-resolved gene expression pattern of Xoo is conserved in both mRNA and protein, there are varied time gaps in genes between the expression peaks of mRNA and protein, which implies there is an additional translational selection step of specific mRNAs for rapid translation. The expression pattern of genes from a polycistronic mRNA in the same gene cluster is strictly conserved. The time-resolved gene expression study of Xoo in both transcriptome and proteome provides a valuable information about the pathogenic responses of Xoo at the initial stage of Xoo-rice interaction.