Comparative transcriptomics reveals unique pine wood decay strategies in the Sparassis latifolia

Sparassis latifolia is a valuable edible mushroom, growing on fresh pine wood sawdust substrate. However, the mechanistic bases are poorly understood. The gene expression profiles of S. latifolia were analyzed from submerged cultures with fresh pine wood sawdust substrate for different time (0 h, 1 h, 6 h, 1 day, 5 days, and 10 days, respectively). The total number of differentially expressed genes (DEGs) identified under pine sawdust inducing was 2,659 compared to 0 h (CK). And 1,073, 520, 385, 424, and 257 DEGs were identified at the five time points, respectively. There were 34 genes in common at all inoculated time points, including FAD/NAD(P)-binding domain-containing protein, glucose methanol choline (GMC) oxidoreductase, flavin-containing monooxygenase, and taurine catabolism dioxygenase. Weighted gene co-expression analysis (WGCNA) was then used to compare the molecular characteristics among the groups and identified that the blue module had the highest correlation with the time induced by pine wood sawdust. There were 102 DEGs out of 125 genes in the blue model, which were most enriched in nitronate monooxygenase activity, dioxygenase activity, and oxidation-reduction process GO terms (p < 0.05), and peroxisome in KEGG pathway. This may provide clues into mechanisms that S. latifolia can grow on fresh pine wood sawdust substrate.