12-02: Deciphering regulatory mechanisms associated with hemicellulose degradation in Neurospora crassa

Plant biomass, primarily composed of cellulose and hemicellulose, is widely viewed as a potential feedstock for the production of liquid fuels and other value-added materials. Degradation of insoluble plant cell wall polysaccharides by filamentous fungi requires production of many different enzymes, which are induced by biopolymers or its derivatives and regulated mainly at the transcriptional level through transcription factors (TFs). XLNR/XYR1 in Trichoderma and Aspergillus species is considered to be the major transcriptional regulator of genes encoding cellulases and hemicellulases. To decipher the transcriptional regulatory network involved in hemicellulose deconstruction in the model filamentous fungus Neurospora crassa , we identified the transcriptional regulon of XLNR.  Strains containing deletions in genes within the XLNR regulon were analyzed for phenotypic changes during growth on xylan and for xylanase activity.  Transcriptional analysis has allowed for a comprehensive system level understanding of plant cell wall degradation mechanisms used by filamentous fungi.