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.
Project description:The soil-borne fungal pathogen Fusarium oxysporum f.sp. is responsible for Fusarium wilt. cubense tropical race 4, is one of the most devastating diseases in bananas, regarded as a major yield-reducing factor in the banana industry worldwide. Understanding the molecular interactions in banana defense responses is an important tool to reveal the unexplained processes that underlie banana resistance to Fusarium oxysporum f. sp. cubense tropical race 4. The seedlings of moderately resistant variety Guijiao No. 9 and a susceptible cultivar Guijiao No. 6 were cultured in tissue culture, and the characterize protein profile expression changes responses to after inoculation the Fusarium oxysporum f. sp. of cubense tropical race 4 were detected by isobaric labeling based on MS2 quantification at the 2nd, 4th, 6th and 8th day. Interestingly, new genes in the resistance of banana to Foc37-GFP were identified, including several other serine/threonine-protein kinase, AvrRpt-cleavage domain-containing protein, peptidylprolyl isomerase and some Jacalin-type lectin domain, the resistance-related pathways “ribosome”, “microbial metabolism in diverse environments”,“carbon metabolism”,“biosynthesis of amino acids”and “biosynthesis of antibiotics” pathways were significantly enriched, the resistant banana cultivar Guijiao 9 shows formation of different constitutive cell barriers to restrict spreading of Fusarium oxysporum f. sp. cubense tropical race 4. In this study, the dynamic change root proteomic of moderately resistant cultivar Guijiao 9 and a susceptible cultivar Guijiao 6 were characterized and provided a differentially expressed proteins comparative analysis of the compatible and incompatible interaction between Fusarium oxysporum f. sp. cubense tropical race 4 and banana. These findings provide a substantial contribution to existing sequence resources for banana, and a strong basis for future proteomic research. The proteins that displayed two-fold changes in intensity are related to biochemical processes that may be differentially altered at various times after Fusarium oxysporum f. sp. cubense tropical race 4 infection. These findings will accelerate research on resistance in banana to Fusarium oxysporum f. sp. cubense tropical race 4 and contribute to a better understanding of the banana defense mechanism to plant pathogens, hopefully.
Project description:Deep sequencing of mRNA from Fusarium oxysporum f. sp. Cubense 1 and 4 after infecting Musa acuminata 0h and 48h. Analysis of ploy(A)+ RNA of different hours after infecting of Musa acuminata
Project description:We report the first data of RNA sequencing of banana Musa acuminata cv. Pisang ambon kuning (AAA group) inoculated by two different endophyte bacteria named Stenothropomonas nitritireducens (BR-49) and Kocuria rhizophila (SL-08), respectively, prior to Fusarium oxysprorum f.sp. cubense tropical race 4 (Foc TR4).
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:Background: Banana (Musa) is one of the most important crops grown in tropical and sub-tropical areas. Cavendish, the most widely grown banana cultivar, is a triploid derived from an intra-species cross. Cavendish is relatively resistant to Race 1 of Fusarium oxysporum f. sp. Cubense (Foc1) which caused wide spread Panama disease during 1960s but is susceptible to Race 4 of Foc (Foc4) which has been causing epidemics in large areas of banana fields in Asia and Australia in the last decade and is threatening world banana production. The genome of the diploid species Musa acuminata (AA) which is the ancestor of a majority of cultivated banana has recently been sequenced. Availability of banana transcriptomes will be highly useful for improving banana genome annotation and assembly and for banana biological research. The knowledge of global gene expression patterns influenced by infection by different Foc races will help to understand the pathogenesis processes and the host responses to the infection. Results: RNA samples extracted from different organs of the Cavendish cultivar were pooled for deep sequencing using the Illumina sequencing technology. The assembled reads were aligned with the genome of M. accuminata and with sequences in the Genbank databases. The analysis led to identification of 842 genes that were not annotated by the Musa genome project. A large number of simple nucleotide polymorphisms (SNPs) and short insertions and deletion (indels) were identified from the transcriptome data. GFP-expressing Foc1 and Foc4 was generated and used to monitor the infection process. Digital gene expression (DGE) profiling analysis was carried out to obtain transcriptome profiles influenced by infection with Foc1 and Foc4 in banana roots at 3, 27, and 51 hours post-inoculation. Both Foc1 and Foc4 were found to be able to invade banana roots and spread to root vascular tissues in the first two days following inoculation. The profiling analysis revealed that inoculation with Foc1 and Foc4 caused similar changes in the gene expression profiles in the infected banana roots. The Foc infection led to induction of many well-known defense-related genes including PATHOGENESIS-RELATED 5 (PR5), PAL, and a lignin-forming peroxidase. The WRKY40 gene, which is a negative regulator of the defense pathway in Arabidopsis, was quickly and strongly suppressed by the infection. Two genes encoding the ethylene biosynthetic enzyme ACC oxidase and several ethylene-responsive transcription factors were among strongly induced genes by both Foc1 and Foc4 Conclusions: Both Foc1 and Foc4 are able to spread into the vascular system of banana roots during the first two days of the infection process and their infection led to similar gene expression profiles in banana roots. The transcriptome profiling analysis indicates that the ethylene synthetic and signalling pathways were activated in response to the Foc infection. Digital gene expression (DGE) profiling analysis was carried out to obtain transcriptome profiles influenced by infection with Foc1 and Foc4 in banana roots at 3, 27, and 51 hours post-inoculation. The plants whose roots were immersed in the culture medium without the pathogen (mock inoculation) were used as a control.
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:Nitrogen (N) fertilisers are routinely applied to bananas (Musa spp.) to increase production, but may exacerbate important disease such as Fusarium wilt of banana (FWB). Here, we characterised the effects of N rate and form (ammonium or nitrate) on FWB severity, the banana root proteome, and the diversity of rhizosphere bacterial and fungal communities. Banana plants (Musa ABB) were grown under greenhouse conditions in soil with ammonium or nitrate supplemented at five N rates, and with or without inoculation with Fusarium oxysporum f. sp. cubense (Foc). The growth of non-inoculated plants was positively correlated with N rate. In bananas inoculated with Foc, disease severity increased with N rate, resulting in Foc-inoculated plant growth being greatest at intermediate N rates. The abundance of Foc was weakly related to the treatment conditions and was a poor predictor of disease severity. Fungal diversity was consistently affected by Foc inoculation, while bacterial diversity was associated with changes in soil pH resulting from N addition, in particular ammonium. N rate altered the expression of host metabolic pathways associated with carbon fixation, energy usage, amino acid metabolism, and importantly stress response signalling, irrespective of inoculation or N form. Furthermore, in diseased plants, Pathogenesis-related protein 1, a key endpoint for biotic stress response and the salicylic acid defence response to biotrophic pathogens, was negatively correlated with the rate of ammonium fertiliser but not nitrate. As expected, inoculation with Foc altered the expression of a wide range of processes in the banana plant including those of defence and growth. In summary, our results indicate that the severity of FWB was negatively associated with host defences, which were influenced by N application (particularly ammonium), and shifts in microbial communities in response to ammonium-induced acidification.
Project description:Background: Banana (Musa) is one of the most important crops grown in tropical and sub-tropical areas. Cavendish, the most widely grown banana cultivar, is a triploid derived from an intra-species cross. Cavendish is relatively resistant to Race 1 of Fusarium oxysporum f. sp. Cubense (Foc1) which caused wide spread Panama disease during 1960s but is susceptible to Race 4 of Foc (Foc4) which has been causing epidemics in large areas of banana fields in Asia and Australia in the last decade and is threatening world banana production. The genome of the diploid species Musa acuminata (AA) which is the ancestor of a majority of cultivated banana has recently been sequenced. Availability of banana transcriptomes will be highly useful for improving banana genome annotation and assembly and for banana biological research. The knowledge of global gene expression patterns influenced by infection by different Foc races will help to understand the pathogenesis processes and the host responses to the infection. Results: RNA samples extracted from different organs of the Cavendish cultivar were pooled for deep sequencing using the Illumina sequencing technology. The assembled reads were aligned with the genome of M. accuminata and with sequences in the Genbank databases. The analysis led to identification of 842 genes that were not annotated by the Musa genome project. A large number of simple nucleotide polymorphisms (SNPs) and short insertions and deletion (indels) were identified from the transcriptome data. GFP-expressing Foc1 and Foc4 was generated and used to monitor the infection process. Digital gene expression (DGE) profiling analysis was carried out to obtain transcriptome profiles influenced by infection with Foc1 and Foc4 in banana roots at 3, 27, and 51 hours post-inoculation. Both Foc1 and Foc4 were found to be able to invade banana roots and spread to root vascular tissues in the first two days following inoculation. The profiling analysis revealed that inoculation with Foc1 and Foc4 caused similar changes in the gene expression profiles in the infected banana roots. The Foc infection led to induction of many well-known defense-related genes including PATHOGENESIS-RELATED 5 (PR5), PAL, and a lignin-forming peroxidase. The WRKY40 gene, which is a negative regulator of the defense pathway in Arabidopsis, was quickly and strongly suppressed by the infection. Two genes encoding the ethylene biosynthetic enzyme ACC oxidase and several ethylene-responsive transcription factors were among strongly induced genes by both Foc1 and Foc4 Conclusions: Both Foc1 and Foc4 are able to spread into the vascular system of banana roots during the first two days of the infection process and their infection led to similar gene expression profiles in banana roots. The transcriptome profiling analysis indicates that the ethylene synthetic and signalling pathways were activated in response to the Foc infection.