Project description:Thymol (5-methyl-2-(1-methylethyl) phenol, PubChem CID: 6989) has been extensively reported to have antimicrobial activity against pathogenic microorganisms. In this study, the growth of F. oxysporum was significantly inhibited by thymol in vitro. The dry weight of F. oxysporum was decreased significantly. Thymol-induced cell membrane damage was observed at 24 hpi (hours post incubation). Therefore, the changes in the gene expression level of F. oxysporum after treatment with 80 μg/mL (average EC50 value) of thymol were analyzed using RNA-seq to reveal the underlying fungicidal mechanisms of thymol.
Project description:The biological relevance of the experiment was to mainly understand the F. oxysporum genes that are involved in the colonization of tomato roots during early interaction timepoints of 1, 2, 3 and 7 days post infection as compared to the in vitro grown axenic sample.
Project description:Fusarium oxysporum causes Fusarium wilt syndrome in more than 120 different plant hosts, including globally important crops such as tomato, cotton, banana, melon, etc. F. oxysporum shows high host specificity in over 150 formae speciales and have been ranked in the top 10 plant fungal pathogens. Although three PMTs encoded by the pmt1, pmt2, and pmt4 are annotated in the genome of F. oxysporum, their functions have not been reported. As O-mannosylation is not found in plants, a comprehensive understanding of PMTs in F. oxysporum becomes attractive for the development of new strategy against Fusarium wilt. In order to understand the molecular mechanism of the differential functions of three PMTs, a comparative O-glycoproteome analysis of the pmt mutants were carried out.
Project description:Fusarium oxysporum is one of the most common species causing soybean root rot and seedling blight in the U.S. In a recent study, significant variation in aggressiveness was observed among isolates of F. oxysporum collected from roots in Iowa, ranging from highly pathogenic to weakly or non-pathogenic isolates. In the present work, a RNA-seq-based analysis was used for the first time to investigate the molecular aspect of the interaction of a partially resistant soybean genotype with non-pathogenic/pathogenic isolates of F. oxysporum at 72 and 96 hours post inoculation (hpi). Markedly different gene expression profiles were observed in compatible and incompatible host-pathogen combinations. A peak of differentially expressed genes (DEGs) was observed at 72 hpi in soybean roots in response to both isolates, although the number of DEGs was about eight times higher for the pathogenic isolate compared to the non-pathogenic one (1,659 vs. 203 DEGs, respectively). Furthermore, not only the number of genes, but also the magnitude of induction was much greater in response to the pathogenic isolate. This response included a stronger activation of many well-known defense-related genes, and several genes involved in ethylene biosynthesis and signalling, transcription factors, secondary and sugar metabolism. In addition, 1130 fungal genes were differentially expressed between the F. oxysporum isolates in planta during the infection process. Interestingly, 10% of these genes encode plant cell-wall degrading enzymes, reactive oxygen species-related enzymes and fungal proteins involved in primary metabolic pathways. Such information may be useful in the development of new methods of broadening resistance of soybean to F. oxysporum, including the silencing of important fungal genes, and also to understand the molecular basis of soybean-F. oxysporum interactions. Soybean seedlings mRNA profiles inoculated with a non-pathogenic and pathogenic isolates of F. oxysporum and collected at 72 and 96 hpi, were generated using Illumina HiSeq 2500. Control seedlings were also included for each time of inoculation. Three biological replicates were considered for each condition, 18 samples in total.
Project description:To study whether there are differences in chromatin-mediated regulation between and within chromosomes in Fusarium oxysporum f. sp. lycopersici 4287 (FGSC9935), we determined the distribution of histone marks associated with euchromatin (H3K4me2) and facultative heterochromatin (H3K27me3) in vitro. We then determined whether these differences correlate with differences in dispensability and sequence divergence and gene expression.
Project description:Upon exposure to unfavorable environmental conditions, plants need to respond quickly to maintain their homeostasis. For instance, physiological, biochemical and transcriptional changes occur during plant-pathogen interaction. In the case of Vanilla planifolia Jacks., a worldwide economically important crop, it is susceptible to Fusarium oxysporum f. sp. vanillae. This pathogen causes root and stem rot in vanilla plants that lead to plant death. To investigate how vanilla plants, respond at the transcriptional level upon infection with F. oxysporum f. sp. vanillae, here we employed the RNA-Seq approach to analyze the dynamics of whole-transcriptome changes during two-time frames of the infection. Analysis of global gene expression profiles indicated that the major transcriptional change occurred at 2 dpi, in comparison to 10 dpi. Whereas 3420 genes were found with a differential expression at 2 dpi, only 839 were identified at 10 dpi. The analysis of the transcriptional profile at 2 dpi suggests that, among other responses, vanilla plants prepare to counter the infection by gathering a pool of translational regulation-related transcripts. The screening of transcriptional changes of V. planifolia Jacks upon infection by F. oxysporum f. sp. vanillae provides insights into the plant molecular response, particularly the upregulation of ribosomal proteins at early stages. Thus, we propose that the plant-pathogen interaction between V. planifolia Jacks and F. oxysporum f. sp. vanillae causes a transcriptional reprogramming coupled with a translational regulation. Altogether, this study provides the identification of molecular players that could help to fight the most damaging disease of vanilla.
Project description:Soilborne fungal pathogens cause devastating yield losses, are highly persistent and difficult to control. To culminate infection, these organisms must cope with limited availability of iron. Here we show that the bZIP protein HapX functions as a key regulator of iron homeostasis and virulence in the vascular wilt fungus Fusarium oxysporum. Deletion of hapX does not affect iron uptake, but causes derepression of genes involved in iron-consuming pathways, leading to impaired growth under iron-depleted conditions. F. oxysporum strains lacking HapX are reduced in their capacity to invade and kill tomato plants and immunodepressed mice. The virulence defect of M-NM-^ThapX on tomato plants is exacerbated by coinoculation of roots with a biocontrol strain of Pseudomonas putida, but not with a siderophore-deficient mutant, indicating that HapX contributes to iron competition of F. oxysporum in the tomato rhizosphere. These results establish a conserved role for HapX-mediated iron homeostasis in fungal infection of plants and mammals. Iron dependent gene expression in Fusarium oxysporum wt and M-NM-^ThapX mutant was measured 1 hour after shifting the mycelia to minimal medium with or without 50 M-NM-<M Fe2(SO4)3. Three independent experiments were performed.
Project description:Fusarium oxysporum is one of the most common species causing soybean root rot and seedling blight in the U.S. In a recent study, significant variation in aggressiveness was observed among isolates of F. oxysporum collected from roots in Iowa, ranging from highly pathogenic to weakly or non-pathogenic isolates. In the present work, a RNA-seq-based analysis was used for the first time to investigate the molecular aspect of the interaction of a partially resistant soybean genotype with non-pathogenic/pathogenic isolates of F. oxysporum at 72 and 96 hours post inoculation (hpi). Markedly different gene expression profiles were observed in compatible and incompatible host-pathogen combinations. A peak of differentially expressed genes (DEGs) was observed at 72 hpi in soybean roots in response to both isolates, although the number of DEGs was about eight times higher for the pathogenic isolate compared to the non-pathogenic one (1,659 vs. 203 DEGs, respectively). Furthermore, not only the number of genes, but also the magnitude of induction was much greater in response to the pathogenic isolate. This response included a stronger activation of many well-known defense-related genes, and several genes involved in ethylene biosynthesis and signalling, transcription factors, secondary and sugar metabolism. In addition, 1130 fungal genes were differentially expressed between the F. oxysporum isolates in planta during the infection process. Interestingly, 10% of these genes encode plant cell-wall degrading enzymes, reactive oxygen species-related enzymes and fungal proteins involved in primary metabolic pathways. Such information may be useful in the development of new methods of broadening resistance of soybean to F. oxysporum, including the silencing of important fungal genes, and also to understand the molecular basis of soybean-F. oxysporum interactions.
Project description:To further understand the abnormal phenotype of the calcineurin mutant strains and identify calcineurin-mediated genes in F. oxysporum f. sp. lycopersici, we performed RNA sequencing to compare the transcriptome profiles of the wild-type (WT), Δcna1(HFW1) and Δcnb1 (HFW3) mutants. By pairwise analysis, a total of 2139 genes were differentially expressed between WT and Δcna1 mutant based on the selection criteria of four-fold change in expression (Log2 fold change > 2 or < -2, P < 0.05). Among these, 1079 genes were upregulated and 1060 genes were downregulated. Moreover, from the comparison of WT against Δcnb1 mutant, 1412 gene were being regulated, and 840 genes were upregulated while 572 genes were downregulated. To elucidate genes that were regulated by calcineurin in F. oxysporum f. sp. lycopersici, the gene sets obtained from the pairwise analyses were compared, giving an overlap of 737 genes. Among these, 414 genes were found to be downregulated and 323 were upregulated, indicating that these genes possibly involved in the calcineurin pathway. GO functional analysis showed these transcripts were mainly involved in the oxidation-reduction process, single-organism metabolic process, transporter activity, cofactor binding, and other metabolic and biological processes.
Project description:The colonization of Capsicum annuum roots by Fusarium oxysporum Fo47 induces resistance responses on the plant. Fo47 is a non-pathogenic strain of Fusarium oxysporum. Fo47 colonizes only the most outer layers of the root surface but it does not colonize inner tissues. Pre-treatment of roots with Fo47 reduces the symptom development produced by later pathogen inoculation. The expression of genes in distal tissues was determined by microarray analysis of stems of Fo47-treated plants. Capsicum annuum samples were analyzed using Affymetrix chips of the close-related species Solanum lycopersicum.