Xylanase Gene Transcription in Trichoderma reesei Is Triggered by Different Inducers Representing Different Hemicellulosic Pentose Polymers
- 1 March 2013
- journal article
- research article
- Published by American Society for Microbiology in Eukaryotic Cell
- Vol. 12 (3), 390-398
- https://doi.org/10.1128/ec.00182-12
Abstract
The ascomycete Trichoderma reesei is a paradigm for the regulation and production of plant cell wall-degrading enzymes, including xylanases. Four xylanases, including XYN1 and XYN2 of glycosyl hydrolase family 11 (GH11), the GH10 XYN3, and the GH30 XYN4, were already described. By genome mining, we identified a fifth xylanase, XYN5, belonging to GH11. Transcriptional analysis reveals that the expression of all xylanases but xyn3 is induced by d -xylose, dependent on the cellulase and xylanase regulator XYR1 and negatively regulated by the carbon catabolite repressor CRE1. Impairment of d -xylose catabolism at the d -xylose reductase and xylitol dehydrogenase step strongly enhanced induction by d -xylose. Knockout of the l -xylulose reductase-encoding gene lxr3 , which connects the d -xylose and l -arabinose catabolic pathways, had no effect on xylanase induction. Besides the induction by d -xylose, the T. reesei xylanases were also induced by l -arabinose, and this induction was also enhanced in knockout mutants in l -arabinose reductase ( xyl1 ), l -arabitol dehydrogenase ( lad1 ), and l -xylulose reductase ( lxr3 ). Induction by l -arabinose was also XYR1 dependent. Analysis of intracellular polyols revealed accumulation of xylitol in all strains only during incubation with d -xylose and accumulation of l -arabitol only during incubation with l -arabinose. Induction by l -arabinose could be further stimulated by addition of d -xylose. We conclude that the expression of the T. reesei xylanases can be induced by both d -xylose and l -arabinose, but independently of each other and by using different inducing metabolites.Keywords
This publication has 48 references indexed in Scilit:
- d -Xylose Concentration-Dependent Hydrolase Expression Profiles and the Function of CreA and XlnR in Aspergillus nigerApplied and Environmental Microbiology, 2012
- Deciphering Transcriptional Regulatory Mechanisms Associated with Hemicellulose Degradation in Neurospora crassaEukaryotic Cell, 2012
- L -Arabitol Is the Actual Inducer of Xylanase Expression in Hypocrea jecorina (Trichoderma reesei)Applied and Environmental Microbiology, 2011
- MEGA5: Molecular Evolutionary Genetics Analysis Using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony MethodsMolecular Biology and Evolution, 2011
- Regulation of pentose utilisation by AraR, but not XlnR, differs in Aspergillus nidulans and Aspergillus nigerApplied Microbiology and Biotechnology, 2011
- d -Xylose as a Repressor or Inducer of Xylanase Expression in Hypocrea jecorina ( Trichoderma reesei )Applied and Environmental Microbiology, 2010
- Molecular Regulation of Arabinan and l -Arabinose Metabolism in Hypocrea jecorina ( Trichoderma reesei )Eukaryotic Cell, 2009
- DnaSP v5: a software for comprehensive analysis of DNA polymorphism dataBioinformatics, 2009
- Transcriptional Regulation of xyr1 , Encoding the Main Regulator of the Xylanolytic and Cellulolytic Enzyme System in Hypocrea jecorinaApplied and Environmental Microbiology, 2008
- Relative expression software tool (REST(C)) for group-wise comparison and statistical analysis of relative expression results in real-time PCRNucleic Acids Research, 2002