Multiomics reveals the molecular mechanism of unsaturated fatty acid-induced terpenoid biosynthesis in Sanghuangporus lonicericola.

Treatment with C18:1 and C18:2, but not C18:0, increased the triterpenoid content of the medicinal fungus Sanghuangporus lonicericola. We identified 413 terpenoids, including 210 volatile terpenoids. Eight upregulated terpenoids, including 3,13,15-trihydroxyoleanane-12-one, dulcioic acid and serrat-14-ene-3,20,24,29-tetrol, were shared between the C18:1 and C18:2 treatments but not the C18:0 treatment. The C18:1 and C18:2 treatments increased the levels of 12 and 7 odour-related terpenoids, respectively, and increased the level of alpha-farnesene (herbal odour). Gene set enrichment analysis revealed that compared with C18:0, C18:1 and C18:2 produced stronger activation of the terpenoid biosynthesis, fatty acid degradation, and MAPK signalling pathways and stronger inhibition of basal transcription factors at both the transcript and protein levels. Finally, two-way orthogonal partial least squares analysis revealed that gene and protein expression in the identified pathways was correlated with levels of unsaturated fatty acid-induced terpenoid metabolites. Together, our integrated multiomics data revealed the key pathways involved in unsaturated fatty acid-induced terpenoid biosynthesis in S. lonicericola.