ABSTRACT: Loss of heterochromatin protein 1 (Hep1) in Fusarium graminearum leads to hypervirulence and mycotoxin overproduction during pathogenic growth.
Project description:Upon axenic cultivation in presence of the mycotoxin inducing nitrogen source L- ornithine the HEP1 deletion mutant showed an altered secondary metabolite profile including reduced levels of deoxynivalenol (DON). This finding was contrasted with a 1.5 fold increased infection rate on the susceptible wheat cv. Remus which was accompanied by increased production of DON. Transcriptome analysis of the HEP1 deletion versus the PH-1 wildtype strain during pathogenic growth state as well as during saprophytic growth on dead (non-responding) wheat heads and axenic samples allows to distinguish gene response of the pathogen reacting on signals from the active, defending plant from those regulated by plant substrate effects or in vitro mimicked mycotoxin inducing conditions, providing insights into gene regulation underlying the observed hypervirulence.
Project description:affy_brachy_2011_11 - affy_brachy_2011_11 - Fusarium graminearum is the causal agent of Fusarium head blight (FHB) of small-grain cereals, including wheat. Besides direct grain losses, this disease is of major concern because of the production by the pathogen of mycotoxins which are hazardous to animals, thus making the grain unfit for food or feed. Major mycotoxins produced by the fungus are trichothecens, including deoxynivalenol (DON). In our laboratory, we use Brachypodium distachyon as a model plant for cereals because of its amenability (short life cycle, numerous genomic and genetic resources, ...). We have recently shown that F. graminearum does induce head blight symptoms on this species and that DON is produced on infected spikes. We have also evidenced that a F. graminearum strain unable to produce DON exhibits reduced virulence on B. distachyon spikes, as previously shown on wheat. The aim of this project is to analyse and compare the plant response to DON producing and non-producing strains of F. graminearum. This analysis will allow to decipher the mechanisms of detoxification set up by the plant and also more specific responses due to the impact of the mycotoxin on plant metabolism and physiology. -Three conditions on B. distachyon spikes: 1-Mock inoculation (Tween 20 0,01%) 2-Inoculation by a F. graminearum wild-type strain 3-Inoculation by a F. graminearum mutant strain, unable to produce DON Spikes were point inoculated with 3ul of either Tween 20 0.01%, wild-type strain or mutant strain (300 spores) and incubated for 96 hours. Six inoculated spikes were collected and pooled for each condition and biological replicate. Three independent biological replicates were conducted. 9 arrays - Brachypodium; normal vs disease comparison,time course
Project description:Fusarium head blight (FHB) is a major disease of cereal crops caused by the fungus Fusarium graminearum (Fg). FHB affects the flowering heads (or spikes). This study compare the gene expression profile in wheat spikelets from the very susceptible spring wheat cultivar Roblin inoculated with either water (H2O), a Fg strain (GZ3639) producing the mycotoxin deoxynivalenol (+DON), or a GZ3639-derived Fg strain which has been inactivated at the Tri5 locus (-DON).
Project description:affy_brachy_2011_11 - affy_brachy_2011_11 - Fusarium graminearum is the causal agent of Fusarium head blight (FHB) of small-grain cereals, including wheat. Besides direct grain losses, this disease is of major concern because of the production by the pathogen of mycotoxins which are hazardous to animals, thus making the grain unfit for food or feed. Major mycotoxins produced by the fungus are trichothecens, including deoxynivalenol (DON). In our laboratory, we use Brachypodium distachyon as a model plant for cereals because of its amenability (short life cycle, numerous genomic and genetic resources, ...). We have recently shown that F. graminearum does induce head blight symptoms on this species and that DON is produced on infected spikes. We have also evidenced that a F. graminearum strain unable to produce DON exhibits reduced virulence on B. distachyon spikes, as previously shown on wheat. The aim of this project is to analyse and compare the plant response to DON producing and non-producing strains of F. graminearum. This analysis will allow to decipher the mechanisms of detoxification set up by the plant and also more specific responses due to the impact of the mycotoxin on plant metabolism and physiology. -Three conditions on B. distachyon spikes: 1-Mock inoculation (Tween 20 0,01%) 2-Inoculation by a F. graminearum wild-type strain 3-Inoculation by a F. graminearum mutant strain, unable to produce DON Spikes were point inoculated with 3ul of either Tween 20 0.01%, wild-type strain or mutant strain (300 spores) and incubated for 96 hours. Six inoculated spikes were collected and pooled for each condition and biological replicate. Three independent biological replicates were conducted.
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. Conidiogenesis had been intensively studied in Aspergillus nidulans and regulatory pathway genes have been known to regulate conidiogenesis in stage specific manner. We reported the functional analyses of flbD, abaA, and wetA orthologs in F. graminearum. To understand genome-wide transcriptional profiling of conidiation, we employed RNA-seq of the wild-type Fusarium graminearum Z-3639 and each gene deletion mutants with three time courses (0 h, 6 h and 12 h after induction of conidiogenesis). AbaA experiment: 6 samples examined: 0 h, 6 h and 12 h after induction of conidiogenesis of Fusarium graminearum Z-3639 wild type and ΔabaA(ΔabaA::gen) mutant strains WetA experiment: 3 samples examined: 0 h, 6 h and 12 h after induction of conidiogenesis of Fusarium graminearum ΔwetA(ΔwetA::gen) mutant strains flbD experiment: 3 samples examined: 0 h, 6 h and 12 h after induction of conidiogenesis of Fusarium graminearum ΔflbD(ΔflbD::gen) mutant strains
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. To dissect cellular responses toward heat stress in the plant pathogenic fungus F. graminearum, we compared transcriptomes of the fungal cultures incubated in normal temperature condition (25 ºC) and in high temperature condition (37 ºC) for 15 min. 6 samples examined: 24 h-old mycelia from complete medium (CM) of Fusarium graminearum wild-type Z-3639 were incubated in normal temperature condition (25 ºC) and in high temperature condition (37 ºC) for 15 min.
Project description:We report a complete transcriptomic study of Fusarium graminearum in response to glucose, cellulose, xylan and cell wall fragments with a whole genome microarray from febit. Fusarium graminearum was cultured at 25 °C on minimal M3 medium with glucose, birch wood xylan, carboxy methyl cellulose or hop cell wall as sole carbon source at a concentration of 10 g/L. Microarray experiments were achieved with a Geniom device (febit biomed, Germany). Each of the four tested condition was tested with two biological and two technical replicates.
Project description:The plant pathogenic fungus Fusarium graminearum (Fgr) creates economic and health risks in cereals agriculture. Fgr causes head blight (or scab) of wheat and stalk rot of corn, reducing yield, degrading grain quality and polluting downstream food products with mycotoxins. Fungal plant pathogens must secrete proteases to access nutrition and to breakdown the structural protein component of the plant cell wall. Research into the proteolytic activity of Fgr is hindered by the complex nature of the suite of proteases secreted. We used a systems biology approach comprising genome analysis, transcriptomics and label-free quantitative proteomics to characterise the peptidases deployed by Fgr during growth. A combined analysis of published microarray transcriptome datasets revealed seven transcriptional groupings of peptidases based on in vitro growth, in planta growth, and sporulation behaviours. An orbitrap MS/MS proteomics technique defined the extracellular proteases secreted by Fusarium graminearum.
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. Fhs1 contains a Zn(II)2Cys6 fungal-type DNA-binding domain and localized to nuclei , suggesting that Fhs1 is a transcription factor required for hydroxiurea. 6 samples examined: 24 h after inoculation of Fusarium graminearum wild-type Z-3639 and fhs1 (Îfhs1::GEN) strains in complete media