Transcriptome analysis of Sparassis latifolia cultivated with different carbon sources

Abstract:

[Background] Sparassis latifolia is a valuable edible fungi. However, lignocellulose degradation mechanism is poorly understood. [Objective] To understand expression profiles of lignocellulose degradation associated genes cultivated with different carbon sources. [Methods] Based on RNA sequencing, we obtained the whole-genome expression profiles when the mycelia of S. latifolia were cultured with glucose, cellulose, cellulose/lignin and pine sawdust as the carbon source respectively. Using glucose sample as control, functional analysis of differentially expressed genes was carried out. [Results] Gene ontology enrichment analysis showed that, differently expressed genes which compared to glucose as the sole carbon source were mainly involved in polysaccharide catabolic process, carbohydrate catabolic process, polysaccharide metabolic process and carbohydrate metabolic process. Carbohydrate-active enzymes annotation showed that, transcript levels of genes encoding glycoside hydrolases, thought to be important for hydrolytic cleavage of hemicelluloses and cellulose were mainly influenced by the species of carbon source, and in which genes involved in hemicellulose degradation were mostly up-regulated. Several transcription factor genes up-regulated significantly when the carbon source was cellulose/lignin or pine sawdust respectively. [Conclusion] S. latifolia gene expression pattern is influenced substantially by the species of carbon source. Such adaptations to the carbon source may also reflect fundamental mechanisms by which S. latifolia attack plant cell walls. Our findings provide important information in exploring the potential genes responsible for lignocellulose degradation.