Project description:The aim of this study was to compare the tomato global transcriptional profiles in response to host attack by ToMV and Fol in order to identify genomic differences and similarities in incompatible interactions between a foliar and a vascular pathogen. In order to identify a set of genes of interest in tomato plants infected with F. oxysporum f. sp. lycopersici (Fol) and Tomato Mosaic Virus (ToMV) a transcriptional analysis was performed. Tomato genes differentially expressed upon inoculation with Fol and ToMV were identified at 2 days post-inoculation, using an un-inoculated sample as reference.
Project description:Transcriptome analysis reveals the response mechanism of Frl-mediated resistance to Fusarium oxysporum f. sp. radicis-lycopersici (FORL) infection in tomato
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:RNA interference (RNAi) is a widely-used approach to generate virus-resistant transgenic crops. However, durability of RNAi-mediated resistance under extreme field conditions and side-effects of stable RNAi expression have not been thoroughly investigated. Here we performed field trials and molecular characterization of two RNAi-transgenic Solanum lycopersicum lines resistant to Tomato yellow leaf curl virus (TYLCV) disease, the major constraint for tomato cultivation in Cuba and worldwide. In order to determine potential impact of the hairpin RNA transgene expression on tomato genome expression and development, differences in the phenotypes and the transcriptome profiles between the transgenic and non-transgenic plants were examined. Transcriptome profiling revealed a common set of up- and down-regulated tomato genes, which correlated with slight developmental abnormalities in both transgenic lines.
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 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