Project description:We performed RNA-seq analysis of the root transcriptional response to Fusarium oxysporum f.sp. vasinfectum (FOV) race 4 (FOV4) infection in Gossypium barbadense, also known as Pima cotton. Susceptible Gossypium barbadense inbred lines Pima S-7 (PI 560140) and Pima 3-79 susceptible to Fusarium wilt [Fusarium oxysporum f.sp. vasinfectum (FOV)] race 4 (FOV4), and Pima S-6 (PI 608346) which is resistant to FOV4 infection, were used for the preparation of cDNA libraries and further RNA-seq analyses. An isolate of FOV4 (FOV CA-14) from a naturally infested field in Fresno County in the San Joaquin Valley, California was used in this study.
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:We performed a comparative study to determine the proteome of extracellular vesicles (EVs) from the cotton pathogen Fusarium oxysporum f. sp. vasinfectum (Fov), recovered from two growth conditions in vitro. Label-free quantitative protemics was used to find significant enrichment of proteins between EV samples, the secretome (secreted-soluble proteins) and the cell lysate. Our results show that some proteins were exclusive to EVs and were upregulated compared to the secretome or cell lysate.
Project description:Background: The fungal pathogen, Fusarium oxysporum f.sp. pisi (Fop) causes fusarium wilt in peas. Races 1, 2, 5 and 6 are responsible for the majority of the economic losses globally. These are the only races present in Australia. Molecular infection mechanisms have been studied in a few other F. oxysporum formae speciales however, there has been no Fop-pea pathosystem studies. Results: A transcriptomic study was carried out to understand the molecular pathogenicity differences between the races. Transcript analysis revealed differences in the differentially expressed genes (DEGs) in the Fop races, potentially involved in fungal pathogenicity variations. Most of the DEGs in all the races were engaged in transportation, metabolism, oxidation-reduction, translation, biosynthetic processes, signal transduction, proteolysis, among others. Race 5 expressed the most virulence-associated genes. Most genes encoding for plant cell wall degrading enzymes, CAZymes and effector-like proteins were expressed in race 2. Race 6 had expressed the least number of genes during infection. Conclusion: Fop races deploy various factors and complex strategies to mitigate host defences to facilitate colonisation. This investigation provides an overview of the putative pathogenicity genes in different Fop races during infection. These genes need to be functionally characterised to confirm their pathogenicity/virulence roles and the race-specific genes can be further explored for molecular characterisation.
Project description:Watermelon (Citrullus lanatus) is one of the most important vegetable crops in the world and accounts for 20% of the world’s total area devoted to vegetable production. Fusarium wilt of watermelon is one of the most destructive diseases in watermelon worldwide. Transcriptome profiling of watermelon during its incompatible interactions with Fusarium oxysporum f.sp. niveum (FON) was generated using an Agilent custom microarray which contains 15,000 probes representing approximately 8,200 watermelon genes. A total of 24, 275, 596, 598, and 592 genes that are differentially expressed genes between FON- and mock-inoculated watermelon roots at 0.5, 1, 3, 5 and 8 days post inoculation (dpi), respectively, were identified. Bioinformatics analysis of these differentially expressed genes revealed that during the incompatible interaction between watermelon and FON, the expression of a number of pathogenesis-related (PR) genes, transcription factors, signaling/regulatory genes, and cell wall modification genes, was significantly induced. A number of genes for transporter proteins such as aquaporins were down-regulated, indicating that transporter proteins might contribute to the development of wilt symptoms after FON infection. In the incompatible interaction, most genes involved in biosynthesis of jasmonic acid (JA) showed expressed stronger and more sustained than those in compatible interaction in FON-infected tissues. Similarly, genes associated with shikimate-phenylpropanoid-lignin biosynthesis were also induced in incompatible interaction, but expression of these genes were not changed or repressed in the compatible interaction. Fusarium oxysporum f.sp. niveum induced gene expression in watermelon root was measured at 0.5,1d, 3d, 5d and 8d after inoculation. Sample inoculated with water were used as the mock controls. Three independent experiments were performed.
Project description:Melon RNA-Seq analysis was used to identify candidate resistance genes and to understand the early molecular processes deployed during melon versus Fusarium oxysporum f.sp. melonis Snyd. & Hans race 1.2 (FOM1.2) interaction in the resistant doubled haploid line NAD as opposed to the susceptible genotype Charentais-T at 24 and 48 hours post inoculation (hpi).
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:Watermelon (Citrullus lanatus) is one of the most important vegetable crops in the world and accounts for 20% of the world’s total area devoted to vegetable production. Fusarium wilt of watermelon is one of the most destructive diseases in watermelon worldwide. Transcriptome profiling of watermelon during its incompatible interactions with Fusarium oxysporum f.sp. niveum (FON) was generated using an Agilent custom microarray which contains 15,000 probes representing approximately 8,200 watermelon genes. A total of 24, 275, 596, 598, and 592 genes that are differentially expressed genes between FON- and mock-inoculated watermelon roots at 0.5, 1, 3, 5 and 8 days post inoculation (dpi), respectively, were identified. Bioinformatics analysis of these differentially expressed genes revealed that during the incompatible interaction between watermelon and FON, the expression of a number of pathogenesis-related (PR) genes, transcription factors, signaling/regulatory genes, and cell wall modification genes, was significantly induced. A number of genes for transporter proteins such as aquaporins were down-regulated, indicating that transporter proteins might contribute to the development of wilt symptoms after FON infection. In the incompatible interaction, most genes involved in biosynthesis of jasmonic acid (JA) showed expressed stronger and more sustained than those in compatible interaction in FON-infected tissues. Similarly, genes associated with shikimate-phenylpropanoid-lignin biosynthesis were also induced in incompatible interaction, but expression of these genes were not changed or repressed in the compatible interaction.
Project description:MicroRNAs (miRNAs) are a class of endogenous non-coding small RNAs that regulate targeted mRNAs by degrading or repressing translation, considered as post-transcrption regulators. So far, a large number of miRNAs have been discovered in model plants, but little information is available on miRNAs in banana. In this study, by sequencing the small RNA (sRNA) transcriptomes of Fusarium wilt resistant and susceptible banana varieties, 139 members in 38 miRNA families were discovered, and six out of eight new miRNAs were confirmed by RT-PCR. According to the analysis of sRNA transcriptome data and qRT-PCR verification, some miRNAs were differentially expressed between Fusarium wilt resistant and susceptible banana varieties. Two hundred and ninety-nine and 31 target genes were predicted based on the draft maps of banana B genome and Fusarium oxysporum (FOC1, FOC4) genomes respectively. Specifically, two important pathogenic genes in Fusarium oxysporum genomes, feruloyl esterase gene and proline iminopeptidase gene, were targeted by banana miRNAs. These novel findings may provide a new strategy for the prevention and control of Fusarium wilt in banana.