Project description:Morphology, phylogeny, and sexual stage of Fusarium caatingaense and Fusarium pernambucanum, new species of the Fusarium incarnatum-equiseti species complex associated with insects in Brazil
Project description:Fusarium graminearum and F. verticillioides are devastating cereal pathogens with very different life history and ecological characteristics. F. graminearum is homothallic, and sexual spores are an important component of its life cycle, responsible for disease initiation. F. verticilloides is heterothallic, and produces only modest numbers of fruiting bodies, which are not a significant source of inoculum. To identify corresponding differences in the transcriptional program underlying fruiting body development in the two species, comparative expression was performed, analyzing six developmental stages. To accompany the transcriptional analysis, detailed morphological characterization of F. verticillioides development was performed and compared to a previous morphological analysis of F. graminearum. Morphological development was similar between the two species, except for the observation of possible trichogynes in F. verticillioides ascogonia, which have not been previously reported for any Fusarium species. Expression of over 9000 orthologous genes were measured for the two species. Functional assignments of highly expressed orthologous genes at each time-point revealed the majority of highly expressed genes fell into the M-bM-^@M-^XM-bM-^@M-^Xunclassified proteinsM-bM-^@M-^YM-bM-^@M-^Y category, reflecting the lack of characterization of genes for sexual development in both species. Simultaneous examination of morphological development and stage-specific gene expression suggests that degeneration of the paraphyses during sexual development is an apoptotic process. Expression of mating type genes in the two species differed, possibly reflecting the divergent roles they play in sexual development. Overall, the differences in gene expression reflect the greater role of fruiting bodies in the life cycle and ecology of F. graminearum versus F. verticillioides. mRNA were sampled and compared from six time points across sexual reproduction in two Fusarium species
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 spp. are fungal pathogens of humans and plants. Fusarium oxysporum and Fusarium solani are important species isolated from infections such as onychomycosis, fungal keratitis, invasive infections, and disseminated diseases. These pathologies have a very difficult therapeutic management and poor therapeutic responses, especially in patients with disseminated infection. Little information is available regarding the molecular mechanisms responsible for antifungal resistance in these fungi. methods: In this study, we performed a quantitative analysis of the transcriptional profile of F. oxysporum and F. solani, challenged with amphotericin B (AMB) and posaconazole (PSC) using RNA-seq. Quantitative real-time reverse transcription PCR (qRT-PCR) was used to validate the results results: Several genes related to mechanisms of antifungal resistance such as efflux pumps, ergosterol pathway synthesis, and responses to oxidative stress were found. Genes such as ERG11, ERG5, the Major Facilitator Superfamily (MFS), thioredoxin, and different dehydrogenase genes may explain the reduced susceptibility of Fusarium spp. against azoles and the possible mechanisms that may play an important role in induced resistance against polyenes. conclusions: Important differences in the levels of transcriptional expression were found between F. oxysporum and F. solani exposed to the two different antifungal treatments. Knowledge on the gene expression profiles and gene regulatory networks in Fusarium spp. during exposure to antifungal compounds, may help to identify possible molecular targets for the development of novel, better, and more specific therapeutic compounds. profile transcriptional of Fusarium spp changed to antifungal treatments in vitro
Project description:Fusarium graminearum and F. verticillioides are devastating cereal pathogens with very different life history and ecological characteristics. F. graminearum is homothallic, and sexual spores are an important component of its life cycle, responsible for disease initiation. F. verticilloides is heterothallic, and produces only modest numbers of fruiting bodies, which are not a significant source of inoculum. To identify corresponding differences in the transcriptional program underlying fruiting body development in the two species, comparative expression was performed, analyzing six developmental stages. To accompany the transcriptional analysis, detailed morphological characterization of F. verticillioides development was performed and compared to a previous morphological analysis of F. graminearum. Morphological development was similar between the two species, except for the observation of possible trichogynes in F. verticillioides ascogonia, which have not been previously reported for any Fusarium species. Expression of over 9000 orthologous genes were measured for the two species. Functional assignments of highly expressed orthologous genes at each time-point revealed the majority of highly expressed genes fell into the ‘‘unclassified proteins’’ category, reflecting the lack of characterization of genes for sexual development in both species. Simultaneous examination of morphological development and stage-specific gene expression suggests that degeneration of the paraphyses during sexual development is an apoptotic process. Expression of mating type genes in the two species differed, possibly reflecting the divergent roles they play in sexual development. Overall, the differences in gene expression reflect the greater role of fruiting bodies in the life cycle and ecology of F. graminearum versus F. verticillioides.