SRA

Host-pathogen interactions, in particular during the early stages of infection, are important for the fate of both the invading pathogen and host. In pathogens, these interactions activate diverse pathogenic signals to cause disease in the host and evade the inevitably activated immune responses of the infected host. In this study, we used in vitro assay system and RNA-seq to analyze the time-resolved genome-wide gene expressions of Xanthomonas oryzae pv. oryzae (Xoo) evoked by the interactions with rice leaf extracts. RNA-seq analysis was carried out with samples of 7 different time points within 1 h. The RNA-seq data were verified by qRT-PCR. The in vitro system successfully initiated the pathogenic signals in Xoo cell culture. Many pathogenicity-related genes were expressed within 15 min. The hrpG gene was transcribed at maximum level within 10 min, and hrpX gene expression reached maximum level in 15 min. Chemotaxis and flagellar biosynthesis-related genes and cyclic-di-GMP synthesizing genes having GGDEF motif, were down-regulated until 10 min and after then up-regulated. Genes related to iron uptake and two component systems of phoB-phoR, phoP-phoQ, and pmrA-pmrB were up-regulated before 5 min. Data of multiple time points enabled non-linear regression fit of the time-resolved expression data, with which we newly developed the continuous time-resolved heat map to help the comparison of gene expression profiles. Essentiality of the transcriptionally up-regulated genes was also analyzed by the pathogenicity assay using the Xoo knockout strains, which showed not necessarily all the up-regulated genes were required for pathogenicity. Overall design: the time-dependent, 0, 5, 10, 15, 30, 45, and 60 min, transcriptome analysis of genome-wide Xanthomonas oryzae pv. oryzae genes from the pathogenic interactions with RLX via RNA-Seq