Project description:Pathogenicity of the phytopathogenic enterobacterium Erwinia chrysanthemi, the causative agent of soft rot disease in many plants, is a complex process involving several factors whose production is subject to temporal regulation during infection. After penetrating into its host plant, E. chrysanthemi resides latently in the plant intercellular spaces without provoking any symptoms, and disease occurs only when the environmental conditions are favourable for massive bacterial multiplication and production of plant cell wall degrading enzymes. PecS is a transcriptional regulator of the MarR family that represses production of plant cell wall degrading enzymes. Here, we used microarray analysis to define the PecS regulon and demonstrated that PecS exerts wide-ranging effects on gene expression in E. chrysanthemi. However, the major effects of PecS are largely confined to specific genes that could be linked to pathogenicity and to a group of genes concerned with evading host defences. Among the identified targets are the genes encoding plant cell wall degrading enzymes, secretion systems, the genes involved in flagella synthesis, in biosurfactant synthesis, in oxidative stress response as well as genes encoding toxin-like virulence factors such as NipE and Hemolysin-coregulated proteins. Electromobility shift assays and DNAse I footprinting demonstrated that PecS directly interacts with the regulatory regions of five new targets, ahpC, rhlA, nipE, virK, avrL, that define three different functional classes of genes: oxidative stress response genes (ahpC), biosurfactant synthesis gene (rhlA), genes encoding exported proteins related to other plant associated bacteria proteins (nipE, virK, avrL). Based on this work, we propose a pivotal role of PecS in the switch from a saprophytic to a parasitic lifestyle.
Project description:Hypocrea jecorina (anamorph Trichoderma reesei) is one of the most well studied fungi used in biotechnology industry. This fungus is today a paradigm for the comercial scale production of different plant cell wall degrading enzymes, mainly cellulases and hemicellulases. The objective of this study was to analyze the transcriptional profiling of T. reesei grown in presence of cellulose, sophorose and glucose as the carbon source using RNA-seq approach.
Project description:Hypocrea jecorina (anamorph Trichoderma reesei) is one of the most well studied fungi used in biotechnology industry. This fungus is today a paradigm for the comercial scale production of different plant cell wall degrading enzymes, mainly cellulases and hemicellulases. The objective of this study was to analyze the transcriptional profiling of T. reesei (Δxyr1) grown in presence of cellulose, sophorose and glucose as the carbon source using RNA-seq approach.
Project description:Treatment of rice tissues with purified preparations of a Xanthomonas oryzae pv. oryzae (Xoo) secreted plant cell wall degrading enzyme, Lipase/Esterase (LipA), elicits cell wall damage induced innate immune responses. LipA activity is required for induction of defense responses. In order to characterize the early events during elaboration of cell wall degrading enzyme, Lipase/Esterase (LipA) induced innate immune response in rice, we have performed global gene expression profiling of rice leaves treated with purified LipA at early time points, 30 minutes and 120min, after treatment. Whole genome transcriptional profiling was performed using Affymetrix Rice GeneChips
Project description:V. inaequalis causes apple scab disease, the most economically important disease of apples. In this study, we generated a comprehensive RNA-seq transcriptome of V. inaequalis during host colonization of apple, with six in planta time points (12hpi, 24hpi, 2dpi, 3dpi, 5dpi, 7dpi) and one in culture reference (fungus grown on cellophane membranes overlaying potato dextrose agar). Analysis of this transcriptome identified five in planta gene expression clusters or waves corresponding to three specific infection stages: early, mid and mid-late infection of subcuticular biotrophic host-colonization. In our analysis we focus on general fungal nutrition (plant cell wall degrading enzymes and transporters) as well as effectors (proteinaceous effectors and secondary metabolites). Early infection was characterized by the expression of genes that encode plant cell wall-degrading enzymes (PCWDEs) and proteins associated with oxidative stress responses. Mid-late infection was characterized by genes that encode PCWDEs and effector candidates (ECs).
