Discovery of novel plant biomass conversion associated fungal transcription factors using a network-based approach

Fungal plant biomass conversion (FPBC) is an important component of the global carbon cycle and has been widely applied for the production of biofuels, enzymes and biochemicals. Identification of transcription factors (TFs) governing FPBC is crucial for genetic engineering of industrial fungi towards sustainable production of high-value bioproducts from renewable lignocellulose. Here, we developed a bioinformatics framework for the identification of FPBC related TFs based on reconstructed gene regulatory networks and enrichment analysis of manually curated FPBC gene sets. Applying this approach to model fungi Aspergillus niger and Neurospora crassa, we successfully identified both known TFs and promising candidates. The function of one identified TF, HapX, has been experimentally validated, and several candidates were supported by literature, transcriptome data and initial growth analysis. Our new approach will accelerate the identification of novel TFs involved in FPBC, and facilitate the further improvement of fungal cell factories.