Project description:In order to gain a first insight into the Mycosphaerella graminicola global transcriptome in different nutritional environments, we performed initial experiments on two in vitro growth conditions during log-phase growth and on infected plant material twenty-eight days after inoculation. In vitro log phase growth in nutrient-rich Potato Dextrose Broth (PDB) was used as a control in independent comparisons with 1) log phase growth in nutrient-limiting Czapek-Dox Broth (CDB) and 2) twenty-eight days of plant infection. Growth in PDB results in a rapid budding type growth of the M. graminicola sporidia. Growth in CDB is phenotypically similar in that the fungus continues to grow as budding sporidia but this occurs at approximately 20% of the rate in PDB. In contrast, late stage infected plant material contains fungus growing as filamentous hyphae, generating pycnidia and sporulating. At this stage the plant material is completely senesced and the RNA isolated from this tissue is entirely of fungal origin. The complete lack of plant RNA enabled the microarray comparison to be made against growth in PDB. In order to generate statistically significant data for further analysis sixteen independent microarray blocks were hybridised for each experiment. Within these sixteen replicates were three biological repeats. For data analysis we employed limits of a two-fold cut-off in expression based upon statistical analysis of the replicate hybridisations (P <0.01).
Project description:Z. tritici is a fungal pathogen causing the disease septoria tritici blotch, one of the most economically devastating foliar diseases in wheat. The molecular basis underlying Z. tritici growth, development and pathogenicity is not fully understood yet. Compared to the genomic investigations in this fungus, little is known about the protein expression at a systematic level. The aim of the project is to construct a comprehensive protein database of Z. tritici growing in nutrient-limiting and rich media and in vivo at a late stage of wheat infection by using 1D gel-based and SCX-based proteomics and subproteomics (intracellular and extracellular) approaches.
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. FSS1 contains a Zn(II)2Cys6 fungal-type DNA-binding domain and localized exclusively to nuclei responding to sodium, suggesting that FSS1 is a TF required for sodium tolerance. By RNA-seq and genetic studies, we found a P-type ATPase pump (FgENA5) that is under control of FSS1 and is responsible for phenotypic defects of fss1 mutants. The wild-type, fss1 deletion, fss1 overexpression mutant strains were incubated in potato dextrose broth (PDB) with or without 1 M NaCl supplementation for an hour. 6 samples examined: 1 h after inoculation of Fusarium graminearum wild-type, Δfss1(Δfss1::gen), and fss1 overexpression mutant (fss1::gen-Pef1a-fss1) strains in potato dextrose broth with or without 1 M NaCl supplementation
Project description:Fungi are an important source of enzymes for saccharification of plant polysaccharides and production of biofuels. Understanding of the regulation and induction of expression of genes encoding these enzymes is still incomplete. To explore the induction mechanism, we analysed the response of the industrially important fungus Aspergillus niger to wheat straw, with a focus on events occurring shortly after exposure to the substrate. RNA sequencing showed that over a third of the genes induced after 6 h of exposure to wheat straw were also induced during 6 h of carbon starvation, indicating that carbon starvation is probably an important factor in the early response to wheat straw. The up-regulation of the expression of a high number of genes encoding CAZymes that are active on plant-derived carbohydrates during early carbon starvation suggests that these enzymes could be involved in a scouting role during starvation, releasing inducing sugars from complex plant polysaccharides. Eight samples in total consisting of duplicate shake flask Aspergillus niger cultures from four conditions: 48h glucose, 6 h starvation, 6 h wheat straw, 24 h starvation
Project description:Verticillium dahliae is a soilborne fungus that causes wilt disease in plants. The microsclerotia of V. dahliae produce infectious hyphae that give rise to primary infections. In this study, RNA-seq libraries were prepared from microsclerotia (MS)-producing cultures of V. dahliae (ave = 52.23 million reads), and those not producing microsclerotia (NoMS, ave = 50.58 million reads) and analyzed for differential gene expression.
Project description:Filamentous fungi including mushrooms frequently and spontaneously degenerate during subsequent culture maintenance on artificial media, which shows the loss or reduction abilities of asexual sporulation, sexuality, fruiting and production of secondary metabolites, thus leading to economic losses during mass production. To better understand the underlying mechanisms of fungal degeneration, the model fungus Aspergillus nidulans was employed in this study for comprehensive analyses. First, linkage of oxidative stress to culture degeneration was evident in A. nidulans. Taken together with the verifications of cell biology and biochemical data, a comparative mitochondrial proteome analysis revealed that, unlike the healthy wild type, a spontaneous fluffy sector culture of A. nidulans demonstrated the characteristics of mitochondrial dysfunctions. Relative to the wild type, the features of cytochrome c release, calcium overload and up-regulation of apoptosis inducing factors evident in sector mitochondria suggested a linkage of fungal degeneration to cell apoptosis. However, the sector culture could still be maintained for generations without the signs of growth arrest. Up-regulation of the heat shock protein chaperones, anti-apoptotic factors and DNA repair proteins in the sector could account for the compromise in cell death. The results of this study not only shed new lights on the mechanisms of spontaneous degeneration of fungal cultures but will also provide alternative biomarkers to monitor fungal culture degeneration. Label-free quantitative proteomic analysis of the WT and Sec mt proteins was performed as described previously. Briefly, purified mitochondrial proteins (100 ug) were diluted in the lysis buffer to a concentration of 5 g/ul and carboxyamidomethylated in 50 mM iodoacetamide for 40 min at room temperature in the dark. The proteins were digested with an endoprotease Lys-C (Roche Applied Science, Indianapolis, IN) at a final substrate/enzyme ratio of 100:1 (w/w) at 37 C for 3 h. The Lys-C digests were further treated with modified sequencing grade trypsin (Roche Applied Science, Indianapolis, IN) at a final substrate/enzyme ratio of 50:1 (w/w) at 37 C for 20 h. After digestion, the peptide mixture was passed through an ultra-filter unit (Millipore, Billerica, MA) with a molecular weight cut-off of 10 kDa and acidified by formic acid (0.1% final concentration) for mass spectrum analysis. A linear ion trap-orbitrap liquid chromatography-tandem mass spectrometry system (LTQ-Orbitrap, Thermo Fisher Scientific, San Josse, CA) equipped with a nanospray ion source was used for full MS scan analysis followed by five MS/MS scans in the LTQ on the five most intense ions from the MS spectrum. Three parallel runs were performed consecutively for each sample. The software DeCyder MS (ver 2.0) (GE Healthcare, Pittsburgh, PA) was used to generate the peak lists from all the runs and the data were then automatically searched using the SEQUEST (ver. 2.7) (Thermo Fisher Scientific, San Josse, CA) against the A. nidulans genome archive (ver. S03-M05-R01, containing 10,644 protein entries) at AspGD database (www.aspgd.org) with the following parameters: peptide mass tolerance set to 10 ppm; fragment tolerance set to 0.8 Da, and two missed trypsin cleavages. Carbamidomethylation of cysteine was searched as a fixed modification, whereas N-acetyl protein and oxidation of methionine were searched as variable modifications. For protein identification, all peptide matches were filtered by a maximum false discovery rate (FDR) index less than 0.01, delta Cn larger than 0.1 and Xcorr scores of greater than 1.7, 2.0 and 3.0 for +1, +2, and +3 charged ions, respectively. The peptides were discarded for further analysis if mapped to more than two different proteins. A protein was considered identifiable with at least one unique peptide detected for more than twice in the three replicates of each sample. The MS data have been deposited in the PRIDE proteomics identification database under accession numbers ? List of the identified peptides and matched proteins is provided in Supplemental Table 1. Quantification of proteins was performed by estimating the normalized spectral index (SIN) for each protein, which combines the features of peptide count, spectral count, fragment-ion intensity and protein length as described by Griffin et al.. Reliability of technical repeats was analyzed by calculating the multivariate Pearson correlation coefficients using the software SigmaPlot (ver. 8.0). FDR estimation of differentially expressed proteins was conducted using a mixture model-based method. Heat mapping analysis was conducted using the program Matlab (R2009a). The significance of differentially expressed proteins between the samples was tested with the cutoff values of P less than or equal to 0.05 and FDR less than or equal to 0.05.
Project description:Rhizoctonia solani Kühn is a soilborne basidiomycetous fungus that causes significant damage to many economically important crops. R. solani isolates are classified into 13 Anastomosis Groups (AGs) with interspecific subgroups having distinctive morphology, pathogenicity and wide host range. However, the genetic factors that drive the unique fungal pathology are still not well characterized due to the limited number of available annotated genomes. Therefore, we performed genome sequencing, assembly, annotation and functional analysis of 13 R. solani isolates covering 7 AGs and selected subgroups (AG1-IA, AG1-IB, AG1-IC, AG2-2IIIB, AG3-PT, AG3-TB, AG4-HG-I, AG5, AG6, and AG8). Here, we report a pangenome comparative analysis of 13 R. solani isolates covering important groups to elucidate unique and common attributes associated with each isolate, including molecular factors potentially involved in determining AG-specific host preference. Finally, we present the largest repertoire of annotated R. solani genomes, compiled as a comprehensive and user-friendly database, viz. RsolaniDB. Since 7 genomes are reported for the first time, the database stands as a valuable platform for formulating new hypotheses by hosting annotated genomes, with tools for functional enrichment, orthologs and sequence analysis, currently not available with other accessible state-of-the-art platforms hosting Rhizoctonia genome sequences.
Project description:The project is aimed at analysing the comparitive proteomics of red rot pathogen, C. falcatum, during red rot infection in sugarcane. The differentially abundant proteins shall be used to identify the corresponding genes.
Project description:The induction of genes in response to exposure of T. reesei to wheat straw was explored using genome-wide RNA-seq and compared to published RNA-seq data and model of how A. niger senses and responds to the lignocellulose. After 24 h of exposure to straw, transcript levels of known and predicted lignocellulose-degrading enzymes increased to around 8% of total cellular mRNA in T. reesei, which was much less when compared to A. niger. The bulk of enzymes used to deconstruct wheat straw is similar in both fungi. Other, non-plant cell wall-degrading enzymes which may aid in lignocellulose degradation were also uncovered in T. reesei and similar to those described in A. niger. Antisense transcripts were also shown to be present in T. reesei and their expession can be regulated by the respective growth condition. Triplicate samples of T. reesei cultivated in each of the three following conditions were taken: 1) After 48 h growth in glucose-based minimal media; 2) After transfer of mycelia from glucose-based media into media containing wheat straw as a sole carbon source and 3) 5 h after addition of glucose to straw cultures.
Project description:This study was designed to evaluate the proteome profiles of Phytophthora capsici. We have utilized a proteogenomics pipeline for identification of proteins from P. capsici.