Abstract
The dried sclerotia of Wolfiporia cocos (Schwein.) Ryvarden & Gilb., a traditional Chinese medicine, has triterpenoid as its main active component. Breeding high-yield triterpenoid in W. cocos is an important research topic at present. We screened out two monosporal strains from the same W. cocos 5.78, high-yielding DZAC-Wp-H-29 (H) and low-yielding DZAC-Wp-L-123 (L), and cultured mycelia for 17 days, 34 days, and 51 days, respectively. Transcriptome analysis results showed that triterpenoid synthesis is closely related to gene expression in triterpenoid synthesis pathways (hydroxymethyl glutaryl-CoA reductase (HMGCR), farnesyl diphosphate synthase (FDPS), 4-hydroxybenzoate polyprenyltransferase (COQ2), C-8 sterol isomerase (ERG2), sterol O-acyltransferase (ACAT), tyrosine aminotransferase (TAT), torulene dioxygenase (CAO2), and sterol-4alpha-carboxylate 3-dehydrogenase (erg26)), and is limited by the expression of enzyme M20 combined with domain protein peptide (Pm20d2), aryl-alcohol dehydrogenase (norA), ISWI chromatin-remodeling complex ATPase ISW2, GroES-like protein (adh), cytochrome P450 (ftmP450-1), and unknown proteins unigene0001029 and unigene0011374. In addition, maintaining high triterpenoid accumulation in W. cocos may require a stable membrane structure, so the accumulation ability may be related to the high synthesis ability of sterols. The low accumulation of triterpenoid in W. cocos may be due to the products of key enzymes increasing flow to other pathways.