| description |
Digital gene expression profiling (DGE) was used to compare the responses of Penicillium decumbens strains to different carbon sources including glucose, cellulose and cellulose-wheat bran. In both wild-type strain 114-2 and cellulase hyperproducing mutant JU-A10-T, transcription of lignocellulolytic enzymes were significantly up-regulated in the presense of cellulose. Relative to 114-2, coordinated up-regulation of lignocellulolytic enzymes and down-regulation of amylases and proteases were observed in JU-A10-T, especially in the cellulose-wheat bran medium. The expression of the principal β-glucosidase BGLI gene was not elevated in JU-A10-T, like the cellulases and hemicellulases, suggesting a different regulatory mechanism for this enzyme. Functional analysis of genes up-regulated in JU-A10-T relative to 114-2 also showed enrichment of proteins involved in amino acid synthesis, protein synthesis, and post-translational modification, compatible with the higher level of production of secreted proteins in JU-A10-T.Overall design: Examination of differential gene expressions by Penicillium decumbens strains 114-2 and JU-A10-T grown in three different media. |