Transcriptome analysis of Auricularia fibrillifera fruit-body responses to drought stress and rehydration

Drought stress severely restricts edible fungus production. The genus Auricularia has a rare drought tolerance, a rehydration capability and is nutrient rich. The key genes and metabolic pathways involved in drought-stress and rehydration were investigated using a transcriptome analysis to clarify the relevant molecular mechanisms. Under drought-stress and rehydration conditions, 14,235 and 8,539 differentially expressed genes, respectively, were detected. Ribosome, phagosome, peroxisome, caffeine metabolism, and proline and arginine metabolism, as well as tyrosine metabolic and mitogen-activated protein kinase signaling pathways, had major roles in Auricularia fibrillifera responses to drought stress. Tyrosine and caffeine metabolism might reveal unknown mechanisms for the antioxidation of Auricularia fibrillifera under drought-stress conditions. During the rehydration process, diphenoid biosynthesis, aflatoxin biosynthesis, butanoate metabolism, and C5-branched dibasic acid pathways were significantly enriched. Gibberellins and gamma-aminobutyric acid were important in the recovery of Auricularia fibrillifera growth after rehydration. These findings suggested that the candidate genes and metabolites involved in crucial biological pathways might regulate the drought tolerance or rehydration of Auricularia, shedding light on the corresponding mechanisms and providing new potential targets for the breeding and cultivation of drought-tolerant fungi.