Differential expression of different sex Taxus. mairei under UV-B

Dioecious plants have sex-specific adaptions to constantly changing environments. Ancient gymnosperms have coevolved with diverse endophytic fungi that are essential for the fitness and adaptability of plant host. However, sex-specific impacts on plant-endophyte interaction that affect the environmental stress response are largely unknown. In our study, integrated RNA-seq and ITS analysis was applied to reveal the potential mechanisms underlying the sex-specific UV-B radiation response. RNA-seq data screened a number of differentially expressed genes (DEGs) responsive to UV-B radiation. Enrichment analysis of the DEGs suggested that female T. mairei trees have a slightly stronger response to light stress at transcriptional level. The endophytic fungal communities in T. mairei were significantly affected by both of sex and UV-B radiation. Diversity and hierarchical clustering analyses showed that UV-B radiation was the greater factor in driving differences of fungal communities than sex. Under control condition, the most significant fungal biomarker taxon Pestalotiopsis/Alternaria and Herpotrichiellaceae/Cyphellophora in the female and male trees, respectively. Under UV-B radiation, the genus Guignardia was identified as significant fungal biomarker taxon. To simply the complexity of endophytic fungal communities, 31 genus indicators were identified, including Guignardia and Alternaria.