Project description:The goals of this study are to compare NGS-derived transcriptome profiling (RNA-seq) from grapevine wood infected by a fungal pathogen in the presence of a root biological control agent. One of the goals was to obtain molecular data about the fungus pathogen (Phaeomoniella chlamydospora) during grapevine wood infection. Grapevine pathogen-infected wood mRNA profiles of 2-month-old plantlets (14 days post infection) were generated by deep sequencing, in triplicate, using Illumina Hiseq2500. The sequence reads that passed quality filters were analyzed by TopHat followed by Cufflinks. qRTaPCR validation was performed using SYBR Green assays. Using an optimized data analysis workflow, we mapped sequence reads to the grapevine genome (build IGGP 12x) and identified pathogen transcripts. RNAseq analyses, using a ribosomal RNA depletion technology for library preparation, provided identification of genes expressed by P. chlamydospora during infection: as for genes related to effector biosynthesis enzymes, carbohydrate-active enzymes and transcription regulators involved in known regulation pathways in fungi. Insights about P. oligandrum modulation of grapevine infection by this pathogen were also found. Our study represents the first detailed analysis of grapevine wood infection by a fungal pathogen generated by RNA-seq technology. The optimized data analysis workflows reported here should provide a framework for comparative investigations of expression profiles. Our results show that NGS offers a comprehensive evaluation of mRNA content within grapevine wood tissue. We conclude that RNA-seq based transcriptome characterization would permit the dissection of complex biologic interactions.
Project description:Fomitiporia mediterranea (Fmed) is one of the main fungal species found in grapevine wood rot, also called “amadou”, one of the most typical symptoms of grapevine trunk disease Esca. This fungus is functionally classified as a white-rot, able to degrade all wood structure polymers, i.e., hemicelluloses, cellulose, and the most recalcitrant component, lignin. Specific enzymes are secreted by the fungus to degrade those components, namely carbohydrate active enzymes for hemicelluloses and cellulose, which can be highly specific for given polysaccharide, and peroxidases, which enable white-rot to degrade lignin, with specificities relating to lignin composition as well. Furthermore, besides polymers, a highly diverse set of metabolites often associated with antifungal activities is found in wood, this set differing among the various wood species. Wood decayers possess the ability to detoxify these specific extractives and this ability could reflect the adaptation of these fungi to their specific environment. The aim of this study is to better understand the molecular mechanisms used by Fmed to degrade wood structure, and in particular its potential adaptation to grapevine wood. To do so, Fmed was cultivated on sawdust from different origins: grapevine, beech, and spruce. Carbon mineralization rate, mass loss, wood structure polymers contents, targeted metabolites and secreted proteins were measured. We used the well-known white-rot model Trametes versicolor for comparison. Whereas no significant degradation was observed with spruce, a higher mass loss was measured on Fmed grapevine culture compared to beech culture. Moreover, on both substrates, a simultaneous degradation pattern and the degradation of wood extractives were demonstrated, and proteomic analyses identified a relative overproduction of oxidoreductases involved in lignin and extractive degradation on grapevine cultures, and only few differences in carbohydrate active enzymes. These results could explain at least partially the adaptation of Fmed to grapevine wood structural composition compared to other wood species and suggest that other biotic and abiotic factors should be considered to fully understand the potential adaptation of Fmed to its ecological niche.
Project description:Transcriptional changes occurring at the infection site of 2 weeks old Cabernet sauvignon grapevine cuttings infected with a wood pathogen (Phaeomoniella chlamydospora) in the presence of a root-inoculated biocontrol agent (Pythium oligandrum). Gene expression profiling was done using the Nimblegen whole genome array with 3 biological replicates of 3 pooled wood chunks harvested 0 and 14 d after treatment (pathogen infection, biocontrol agent inoculation, mock treatment).
Project description:Transcriptome profiling by RNA sequencing determined the genome-wide patterns of expression of N. parvum virulence factors when PDA or grape wood were provided as nutrient source and during an extensive interaction time course with grapevine stem.
Project description:Proteomic analysis of the microbiome of beetle intestinal content from wood eating beetles as related to lignocellulose deconstruction and colony subsistence
2019-01-18 | PXD012200 | Pride
Project description:Rapid reprogramming of grapevine wood transcriptomics in response pathogens
Project description:MicroRNAs (miRNAs) are a class of non-coding RNA molecules which have significant gene regulation roles in organisms. The advent of new high throughput sequencing technologies has enabled the revelation of novel miRNAs. Although there are two recent reports on high throughput sequencing analysis of small RNA libraries from different organs of two grapevine wine varieties, there were significant divergence in the number and kinds of miRNAs sequenced in these studies. More sequencing of small RNA libraries is still important for the discovery of novel miRNAs in grapevine. Here, we initially constructed a small RNA library of flower and fruit tissues of a table grapevine cultivar ‘Summer Black’ and performed sequencing and analysis of sRNAs using the Illumina Solexa platform, expecting to discover more miRNAs related to the development of grapevine flowers and berries and the formation of dessert quality in grapevine berries. Totally, 130 conserved grapevine miRNA (Vv-miRNA) belonging to 28 Vv-miRNA families were validated, and 92 novel potential grapevine-specific ones representing 80 unique ones were first discovered. Forty-two (48.84%) of the novel miRNAs possessed differential semi-quantitative PCR expression profiles in various grapevine tissues that could further confirm their existence in the grapevine, among which twenty were expressed only in grapevine berries, indicating some fruit-specificity. 130 target genes for 46 novel miRNAs could be predicted. The locations of these potential target genes on grapevine chromosomes and their complementary levels with the corresponding miRNAs were also analyzed.