Project description:Agaricomycetes produce the most efficient enzyme systems to degrade wood and the most complex morphological structures in the fungal kingdom. Despite decades-long interest in their genetic bases, the evolution and functional diversity of both wood-decay and fruiting body formation are incompletely known.Here, we perform comparative genomic and transcriptomic analyses of wood-decay and fruiting body development in Auriculariopsis ampla and Schizophyllum commune (Schizophyllaceae), species with secondarily simplified morphologies and enigmatic wood-decay strategy and weak pathogenicity to woody plants. The plant cell wall degrading enzyme repertoires of Schizophyllaceae are transitional between those of white rot species and less efficient wood-degraders such as brown rot or mycorrhizal fungi. Rich repertoires of suberinase and tannase genes were found in both species, with tannases restricted to Agaricomycetes that preferentially colonize bark-covered wood, suggesting potential complementation of their weaker wood-decaying abilities and adaptations to wood colonization through the bark. Fruiting body transcriptomes of A. ampla and S. commune revealed a high rate of divergence in developmental gene expression, but also several genes with conserved developmental expression, including novel transcription factors and small-secreted proteins, some of the latter might represent fruiting body effectors. Taken together, our analyses highlighted novel aspects of wood-decay and fruiting body development in a widely distributed family of mushroom-forming fungi.
Project description:Wood-degrading fungi vary in their strategies for deconstructing wood, and their competitive successes shape the rate and fate of carbon released from wood, Earth’s largest pool of aboveground terrestrial carbon. In this study, one-on-one interspecific interactions between two model brown rot (carbohydrate-selective) fungi, Gloeophyllum trabeum and Rhodonia (Postia) placenta, were studied on wood wafers where a clearly resolved interaction zone (IZ) could be generated, reproducibly. Comparative RNAseq and proteomics between the IZ and non-interacting hyphae of each species identified combative strategies for each fungus. Glycoside hydrolases were a relatively smaller portion of the interaction secretome compared to non-interacting hyphae. The interaction zone showed higher pectinase specific activity than all other sampling locations, and higher laminarinase specific activity (branched β‐glucan proxy) was seen in the IZ secretome relative to equivalent hyphae in single‐species cultures. Our efforts also identified two distinct competitive strategies in these two fungi with a shared nutritional mode (brown rot) but polyphyletic ancestral lineages. Gloeophyllum trabeum (Gloeophyllum clade) employed secondary metabolite (SM) synthesis in response to a competitor, as shown by the upregulation of several SM-synthesizing genes in the interaction. R. placenta (Antrodia clade) instead upregulated a larger variety of uncharacterized oxidoreductases in interacting hyphae, suggesting that an oxidative burst may be a response to competitors in this fungus. Both species produced several hypothetical proteins exclusively in the interaction zone, leaving abundant unknowns on the battlefield. This work supports the existence of multiple interaction strategies among brown rot fungi and highlights the functional diversity among wood decay fungi.
Project description:The Trametes versicolor genome is predicted to encode many enzymes that can effectively degrade lignin, making it a has potentially useful application intool for biopulping and biobleaching. Poplar is an important and widely cultivated species of tree species, which isand extensively applied used in the pulping industry. However, the wood degradation mechanism of T. versicolor from transcriptomic level is not clear. To reveal identify the enzymes that contributeing to lignocellulose degraredauction and its degradation mechanisms, we evaluated transcriptomic how study theof T. versicolor transcriptome was changes during evaluated growthing on the poplar wood relative to growth on glucose medium. 853 genes were differentially expressed;, 360 genes were up-regulated on poplar wood, and 493 genes were down-regulated on poplar wood. Notably, most genes relative involved into lignin degradation were up-regulated, including eight lignin peroxidase (LiP) genes, and two manganese peroxidase (MnP) genes etc. Genes encoding cellulose and hemicelluloses degrading-enzymesation were mostly down-regulated, including six endo-β-1, 4-glucanase genes, three cellobiohydrolase I genes, and one cellobiohydrolase II gene, etc. MeanwhileAdditionally, expression of more significant expansion of P450s in T. versicolor genome, along with differences in carbohydrate- and lignin-degrading enzymes, could bewere correlated withto poplar wood degradation. Our results revealed transcriptomic characterizeation transcriptomic changes related toof lignocellulose degradation. Therefore, our results cwould be benuseful for the development ofefit T. versicolor as a tool to improve the efficiency of lignin degradation, and provide a theoretical foundation for a new paper pulp manufacturing processe 1,T.versicolor groewn on PDA medium. 2, T. versicolor growing on the a glucose carbon medium of glucose. 3, T. versicolor growing on poplar medium
Project description:The Trametes versicolor genome is predicted to encode many enzymes that can effectively degrade lignin, making it a has potentially useful application intool for biopulping and biobleaching. Poplar is an important and widely cultivated species of tree species, which isand extensively applied used in the pulping industry. However, the wood degradation mechanism of T. versicolor from transcriptomic level is not clear. To reveal identify the enzymes that contributeing to lignocellulose degraredauction and its degradation mechanisms, we evaluated transcriptomic how study theof T. versicolor transcriptome was changes during evaluated growthing on the poplar wood relative to growth on glucose medium. 853 genes were differentially expressed;, 360 genes were up-regulated on poplar wood, and 493 genes were down-regulated on poplar wood. Notably, most genes relative involved into lignin degradation were up-regulated, including eight lignin peroxidase (LiP) genes, and two manganese peroxidase (MnP) genes etc. Genes encoding cellulose and hemicelluloses degrading-enzymesation were mostly down-regulated, including six endo-β-1, 4-glucanase genes, three cellobiohydrolase I genes, and one cellobiohydrolase II gene, etc. MeanwhileAdditionally, expression of more significant expansion of P450s in T. versicolor genome, along with differences in carbohydrate- and lignin-degrading enzymes, could bewere correlated withto poplar wood degradation. Our results revealed transcriptomic characterizeation transcriptomic changes related toof lignocellulose degradation. Therefore, our results cwould be benuseful for the development ofefit T. versicolor as a tool to improve the efficiency of lignin degradation, and provide a theoretical foundation for a new paper pulp manufacturing processe
Project description:Wood-degrading fungi play a critical role in global carbon cycling, and their varied mechanisms for deconstruction offer pathways for industrial bioconversion. In this study, we used comparative genomics to isolate upregulation patterns among fungi with brown rot (carbohydrate-selective) or white rot (lignin-degrading) nutritional modes. Specifically, we used whole-transcriptome profiling to compare early, middle, and late decay stages on wood wafers, matching differentially-expressed gene (DEG) patterns with fungal growth and enzyme activities. This approach highlighted 34 genes uniquely upregulated in early brown rot stages, with notable candidates involved in generating reactive oxygen species (ROS) as a pretreatment mechanism during brown rot. This approach further isolated 18 genes in late brown rot stages that may be adapted to handle oxidatively-reacted lignocellulose components. By summing gene expression levels in functional classes, we also identified a broad and reliable distinction in glycoside hydrolase (GH) versus lignocellulose oxidative (LOX) transcript counts that may reflect the energy investment burden of lignin-degrading machinery among white rot fungi.
Project description:Polycyclic aromatic hydrocarbons (PAHs) are a class of hundreds of structurally similar chemicals ubiquitously present in our environment. They are created during the incomplete combustion of organic materials, such as oil, wood, tobacco, and charbroiled meat. As such, human exposure to mixtures of PAHs can occur through consumption of PAH-containing foods and water, inhalation of polluted air, or dermal contact. Several PAHs have been classified as carcinogenic to humans or probably carcinogenic to humans by the International Agency for Research on Cancer. The mice in this study were exposed to a complex mixture of PAHs - coal tar. In the present study, we sought to determine the dose-dependent changes in gene expression upon oral exposure to this PAH mixture in the lung tissue. Adult male MutaTMMouse were exposed to three doses of the coal tar or vehicle control (olive oil) for 28 days and sacrificed three days after the final exposure.