Project description:Trichoderma reesei is used to produce saccharifying enzyme cocktails for biofuels. There is limited understanding of the transcription factors (TFs) that regulate the release and catabolism of L-arabinose and D-galactose, as the main TF XYR1 is only partially involved. The T. reesei ortholog of ARA1 from Pyricularia oryzae that regulates L-arabinose release and catabolism, was deleted and characterized by growth profiling and transcriptomics along with a xyr1 mutant and xyr1/ara1 double mutant. Our results show that, in addition to the L-arabinose-related role, T. reesei ARA1 is essential for D-galactose release and catabolism, while XYR1 is not involved in this process.
Project description:In this study we identified the L-arabinose-responsive regulator of Pyricularia oryzae that regulates L-arabinose release and catabolism. Previously we identified the Zn2Cys6 transcription factor (TF) AraR that has this role in the Trichocomaceae family (Eurotiales), but is absent in other fungi. Candidate Zn2Cys6 TF genes were selected according to their transcript profiles on L-arabinose. Deletion mutants of these genes were screened for their growth phenotype on L-arabinose. One mutant, named Δara1, was further analyzed. Our analysis demonstrated that Ara1 from P. oryzae is the functional homolog of AraR from A. niger, while sequence analysis did not reveal significant homology between them.