Project description:We investigated the ascomycete truffle Tuber melanosporum exploits DNA methylation and transcription to cope with the more than 45,000 repeated elements that are present in its genome. Whole-genome bisulfite sequencing and RNA-sequencing, were performed on different developmental stages of this symbiotic hypogeous fungus -fruitbody (FB), free-living mycelium (FLM), and ectomycorrhiza. Examination of DNA methylation and transcription of truffle in its free living mycelium (FLM), fruit body (FB), and ectomycorrhizal root tips (ECM)
Project description:We investigated the ascomycete truffle Tuber melanosporum exploits DNA methylation and transcription to cope with the more than 45,000 repeated elements that are present in its genome. Whole-genome bisulfite sequencing and RNA-sequencing, were performed on different developmental stages of this symbiotic hypogeous fungus -fruitbody (FB), free-living mycelium (FLM), and ectomycorrhiza.
Project description:Truffles are ascomycete hypogeous fungi belonging to the Tuberaceae family of the Pezizales order that grow in ectomycorrhizal symbiosis with tree roots and are known for their peculiar aromas and flavors. Axenic culture of truffle mycelium is problematic because it is not possible in many cases, and the growth rate is meager when it is possible. This limitation prompts searching and characterizing new strains that can be handled in laboratory conditions for basic and applied studies. In this work, a new strain of Tuber borchii (strain SP1) has been isolated and cultured, and its transcriptome has been analyzed under different in vitro culture conditions. The results show that the best T. borchii SP1 growth was obtained using maltose-enriched cultures made with soft-agar and in static submerged cultures made at 22ºC. The transcriptome analysis of this strain cultured in different media indicated that most of the gene transcription effort is due to a limited number of genes (20% of genes account for 80% of the transcription), that the transcription profile of the central metabolism genes was similar in the different conditions analyzed with a transcription signal detected for around 80% of the annotated genes. The gene expression profile suggests that T. borchii uses a fermentative rather than respiratory metabolism, even in aerobic conditions. Finally, there is a reduced expression of genes belonging to secondary metabolite clusters, whereas there is a significative transcription of those involved in producing volatile aromatic compounds.
Project description:Truffles are among the most expensive foods available in the market, usually used as flavoring additives for their distinctive aroma. The most valuable species is Tuber magnatum Pico, better known as 'Alba white truffle', in which bis(methylthio)methane is the key aroma compound. Given the high economical value of genuine white truffles, analytical approaches are required to be able to discriminate between natural or synthetic truffle aroma. With the proteomic approach based on 2-DE followed by mass spectrometry, we were able to identify proteins specifically linked to sample origin. We further associated the proteomic results to an RNA-seq profiling, which confirmed the possibility to differentiate samples according to their source and provided a basis for the detailed analysis of genes involved in a specific metabolism, that of sulfur compounds. Finally, geographical specificities could be associated to the set of volatile compounds produced by the fruiting bodies, as quantitatively and qualitatively determined through PTR-MS and GC-MS. In particular, a PLS-DA model built from the latter data was able to return high confidence predictions of sample source.
Project description:BACKGROUND: The ESTuber database (http://www.itb.cnr.it/estuber) includes 3,271 Tuber borchii expressed sequence tags (EST). The dataset consists of 2,389 sequences from an in-house prepared cDNA library from truffle vegetative hyphae, and 882 sequences downloaded from GenBank and representing four libraries from white truffle mycelia and ascocarps at different developmental stages. An automated pipeline was prepared to process EST sequences using public software integrated by in-house developed Perl scripts. Data were collected in a MySQL database, which can be queried via a php-based web interface. RESULTS: Sequences included in the ESTuber db were clustered and annotated against three databases: the GenBank nr database, the UniProtKB database and a third in-house prepared database of fungi genomic sequences. An algorithm was implemented to infer statistical classification among Gene Ontology categories from the ontology occurrences deduced from the annotation procedure against the UniProtKB database. Ontologies were also deduced from the annotation of more than 130,000 EST sequences from five filamentous fungi, for intra-species comparison purposes. Further analyses were performed on the ESTuber db dataset, including tandem repeats search and comparison of the putative protein dataset inferred from the EST sequences to the PROSITE database for protein patterns identification. All the analyses were performed both on the complete sequence dataset and on the contig consensus sequences generated by the EST assembly procedure. CONCLUSION: The resulting web site is a resource of data and links related to truffle expressed genes. The Sequence Report and Contig Report pages are the web interface core structures which, together with the Text search utility and the Blast utility, allow easy access to the data stored in the database.