Transcriptomic analysis of Hericium erinaceus mycelia at distinct growth stages: insights into molecular mechanisms...

Hericium erinaceus, a highly valued edible fungus, is among the most widely consumed mushrooms globally, attributed to its superior nutritional composition and delicate organoleptic properties. Extensive prior studies have consistently shown that the yield of mature H. erinaceus fruiting bodies is tightly linked to mycelial growth status. Mycelia serve as the essential vegetative structure that supports nutrient acquisition and subsequent reproductive development. To decipher the molecular mechanisms regulating H. erinaceus mycelial growth, transcriptome profiling was conducted on mycelial samples from strains with divergent growth rates, harvested at distinct growth stages. Transcriptomic analysis identified 3,257 DEGs across the two genotypic groups. Notably, upregulated DEGs outnumbered downregulated ones significantly, indicating a predominantly activated transcriptional program during mycelial growth. GO functional annotation revealed these DEGs were primarily enriched in terms related to oxidoreductase activity, which is an enzymatic function critical for mediating redox reactions in energy metabolism and secondary metabolite biosynthesis. KEGG pathway enrichment analysis further showed that most DEGs were concentrated in amino acid metabolism pathways, including arginine and proline metabolism, phenylalanine metabolism, and tryptophan metabolism. These pathways are pivotal for supplying essential nitrogen sources, regulating cellular osmotic balance, and synthesizing bioactive molecules that support mycelial proliferation. Collectively, this study generates comprehensive transcriptomic data for H. erinaceus mycelia, which not only offer valuable insights into the molecular mechanisms driving mycelial growth but also facilitate the identification of key candidate genes regulating mycelial development. These findings establish a robust theoretical basis for optimizing stable large-scale cultivation of H. erinaceus and advancing molecular-assisted breeding to improve its agronomic traits.