Project description:In this study, we showed that three bacteria were able to inhibit the mycelial growth of the phytopathogenic fungus Thielaviopsis ethacetica, by the emission of microbial volatile organic compounds (mVOCs). Aiming to understand the molecular mechanisms of these interactions, we evaluated the transcriptomic response of T. ethacetica to the mVOCs produced by one of these bacterial isolates.
Project description:Communication between interacting organisms via bioactive molecules is widespread in nature and plays key roles in diverse biological processes. Small RNAs (sRNAs) can travel between host plants and filamentous pathogens to trigger trans-kingdom RNA interference (RNAi) in recipient cells and modulate plant defense and pathogen virulence. However, how trans-kingdom RNAi is regulated has rarely been reported. Here, we show that the secretory protein VdSSR1 (secretory silencing repressor 1) from Verticillium dahliae, a soil-borne phytopathogenic fungus that causes wilt diseases in a wide range of plant hosts, is required for fungal virulence in plants through the suppression of trans-kingdom RNAi.
Project description:Amycolatopsis sp. BX17 is an actinobacterium isolated from milpa soils that antagonizes the phytopathogenic fungus Fusarium graminearum. Metabolites secreted by the actinobacterium cultured in medium without glucose inhibited 100% the mycelial growth of F. graminearum RH1, while in medium supplemented with 20 g/L of glucose inhibition was 65%. With the aim of studying how the metabolism of strain BX17 is modulated by glucose, as the main carbon source, media with 0 and 20 g/L glucose were selected to analyze the intracellular proteins by quantitative label-free proteomic analysis.
Project description:Powdery mildew, caused by the fungus Blumeria graminis (DC) Speer, is one of the most important foliar diseases of cereals worldwide. It is an obligate biotrophic parasite, colonising leaf epidermal cells to obtain nutrients from the plant cells without killing them. Syringolin A (sylA), a circular peptide secreted by the phytopathogenic bacterium Pseudomonas syringae pv. syringae, triggers a hypersensitive cell death reaction (HR) at infection sites when sprayed onto powdery mildew infected wheat which essentially eradicates the fungus. The rational was to identify genes whose expression was specifically regulated during HR, i.e. genes that might be involved in the switch of compatibility to incompatibility.<br>Powdery mildew-infected or uninfected plants were treated with syringolin two days after infection and plant material for RNA extraction was collected at 0.5, 1, 2, 4, 8, 12 hours after treatment (hat), resulting in an early (2 and 4 hat) and late pool (8 and 12 hat). Plant material that was uninfected prior to syringolin treatment was collected 8 and 12 hat (late pool of uninfected plant material), and 1 hat, respectively.