Multi-omics Analysis of Fungal Elicitor (Aspergillus R15)-controlled Defense Response and Taxol Biosynthesis of Taxus mairei

Taxol is a well-known and effective antitumor drug extracted from the natural Taxus trees. Due to its extremely low concentration, considerable effort has been invested in exploring methods to enhance the accumulation of Taxol in these trees. Recently, endophytic fungi have been reported to be elicitors in Taxol production. However, the regulatory mechanisms governing the infection process and the enhancement of secondary metabolism remain unclear. In the present study, a fungal elicitor (R15) for Taxol biosynthesis was applied to investigate the responses of T. mairei to fungal infection. Multi-omic analysis revealed that R15 infection significantly up-regulated the transcription levels of several genes related to Taxol biosynthesis while down-regulating the translation efficiencies of numerous defense response genes. The inhibition of defense responses and induction of secondary metabolism occur at the transcription and translation levels, respectively. Furthermore, R15 inhibited the translation of mitochondrial and chloroplast protein-encoding genes, providing a compelling explanation for how R15 successfully completes infection without triggering a defense response in the host plant. Notably, the translation efficiencies of two N6-methyladenosine (m6A) methylation-related genes, MT-A70-like and METTL, were significantly inhibited by R15 infection, suggesting a substantial variation in the m6A methylation level after R15 infection. Variations in m6A levels may lead to inconsistencies in the transcription and translation processes of T. mairei. Our data provides new insights into the interaction of fungi and Taxus trees, as well as the enhancement of Taxol biosynthesis in the Taxus genus.