Project description:Transcript profiles of H. annosum from mycelium grown on different substrates and under different stresses were analyzed. The array probes were designed from gene models taken from the Joint Genome Institute (JGI, department of energy) H. irregulare genome sequence version 1. One aim of this study was to compare gene expression profiles of H. annosum pre-grown on secondary metabolites from the biocontrol agent Phlebiopsis gigantea.
Project description:Transcript profiles of H. annosum from mycelium grown on different substrates and under different stresses were analyzed. The array probes were designed from gene models taken from the Joint Genome Institute (JGI, department of energy) H. irregulare genome sequence version 1. One aim of this study was to compare gene expression profiles of H. annosum pre-grown on secondary metabolites from the biocontrol agent Phlebiopsis gigantea. We performed six hybridizations with samples derived from H. annosum grown in either liquid Malt Extract Medium (three biological replicates) or on secondary metabolite from Phlebiopsis gigantea (three biological replicates). The Heterobasidion irregulare custom-exon expression array (4 x 72K) manufactured by Roche NimbleGen Systems Limited (Madison, WI) (http://www.nimblegen.com/products/exp/index.html) contained five independent, non-identical, 60-mer probes per gene model coding sequence. For 12,199 of the 12,299 annotated protein-coding gene models, probes could be designed. For 19 gene models, no probes could be generated, and 81 gene models shared all five probes with other gene models. Included in the array were 916 random 60-mer control probes and labelling controls. For 2032 randomly chosen gene models, technical duplicates were included on the array.
Project description:Collectively classified as white-rot fungi, certain basidiomycetes efficiently degrade the major structural polymers of wood cell walls. A small subset of these Agaricomycetes, exemplified by Phlebiopsis gigantea, is capable of colonizing freshly exposed conifer sapwood despite its high pitch content, which retards the establishment of other fungal species. The mechanism(s) by which P. gigantea tolerates and metabolizes resinous compounds have not been explored. Here, we report the annotated P. gigantea genome and compare profiles of its transcriptome and secretome when cultured on fresh-cut versus solvent-extracted loblolly pine. The P. gigantea genome contains a conventional repertoire of hydrolase genes involved in cellulose/hemicellulose degradation, whose patterns of expression were relatively unperturbed by the absence of extractives. The expression of genes typically ascribed to lignin degradation was also largely unaffected. In contrast, genes likely involved in the transformation and detoxification of pitch were highly induced in its presence. Their products included an ABC transporter, lipases, cytochrome P450s, glutathione S-transferase and aldehyde dehydrogenase. Other regulated genes of unknown function and several constitutively expressed genes are also likely involved in P. gigantea’s pitch metabolism. These results contribute to our fundamental understanding of conifer colonization and carbon cycling processes. Phlebiopsis gigantea was cultivated in media containing one of three carbon sources: freshly harvested loblolly pine (3 replicates), acetone extracted lobollly pine (3 replicates), or glucose (2 replicates). RNA was extracted and processed for Illumina sequencing as described below.
Project description:Mass spectrometric analysis of extracellular proteins in culture filtrate was performed to elucidate the mechanisms of extractive degradation by Phlebiopsis gigantea of microcrystalline cellulose coated and uncoated with an acetone extract from the Pinus taeda (loblolly pine)
Project description:Collectively classified as white-rot fungi, certain basidiomycetes efficiently degrade the major structural polymers of wood cell walls. A small subset of these Agaricomycetes, exemplified by Phlebiopsis gigantea, is capable of colonizing freshly exposed conifer sapwood despite its high pitch content, which retards the establishment of other fungal species. The mechanism(s) by which P. gigantea tolerates and metabolizes resinous compounds have not been explored. Here, we report the annotated P. gigantea genome and compare profiles of its transcriptome and secretome when cultured on fresh-cut versus solvent-extracted loblolly pine. The P. gigantea genome contains a conventional repertoire of hydrolase genes involved in cellulose/hemicellulose degradation, whose patterns of expression were relatively unperturbed by the absence of extractives. The expression of genes typically ascribed to lignin degradation was also largely unaffected. In contrast, genes likely involved in the transformation and detoxification of pitch were highly induced in its presence. Their products included an ABC transporter, lipases, cytochrome P450s, glutathione S-transferase and aldehyde dehydrogenase. Other regulated genes of unknown function and several constitutively expressed genes are also likely involved in P. gigantea’s pitch metabolism. These results contribute to our fundamental understanding of conifer colonization and carbon cycling processes.
Project description:Insect pathogenic fungus Beauveria bassiana in one of the best studied insect biocontrol fungus, which infects insects by cuticle penetration. After breaking the cuticles, the fungus will propagate in insect hemocoel and kill insect hosts. It has also been found that the mycelia of B. bassiana can penetrate plant tissues to reach insect inside plant, e.g. corn borer (Ostrinia furnacalis), but do not cause damage to plants. The mechanism of fungal physiological plasticity is poorly understood. To accompany our genome sequencing work of B. bassiana strain ARSEF 2860, fungal transcriptional responses to different niches were studied using an Illumina RNA_seq technique. To examine fungal response to insect cuticle, conidia were inoculated on locust hind wings for 24 hours before used for RNA extraction. To evaluate fungal adaptation to insect hemocole, the fifth instar larvae of cotton bollworms were injected with spore suspension and fungal cells isolated by centrifugation in a step gradient buffer. To unveil the mechanism of interaction with plants, the fungus was grown in corn root exudates for 24 hours. After RNA sequencing, around three million tags were acquired for each sample and fungal transcriptional profiles were compared. Unveiling gene differential expression patterns when the insect biocontrol fungus Beauveria bassiana grown in insect hemocoel, corn root exudates and on insect cuticles.
Project description:The plant recognition specific PCA cluster mediates early chemical communication between plant and fungus, is required for colonization and it is likely responsible for the high potential of T. harzianum and closely related species for biocontrol applications.