Integration analysis of full-length transcriptomics and metabolomics provides new insights into the mechanism of sex differentiation inbuffalograss (<i>Buchloe dactyloides</i>)

Abstract

The study of sexual and evolutionary differences has long been imperative in the field of biology. Unlike animals, dioecious angiosperms account for only about 6% of the total. Buffalograss (Buchloe dactyloides) plays a vital role in environmental restoration, creating economic benefits and promoting the high-quality development of the grassland and turf industries. Its natural populations contain differing ratios of male, female, and monoecious plants. The value of buffalograss for studying the sex differentiation mechanism in plants cannot be ignored. However, few studies have investigated transcript annotation and complete mRNA structure in B. dactyloides, and the pathways of species-specific factors in sex differentiation remain unknown. We integrated the full-length transcriptome, second-generation transcriptome, and metabolome to specify candidate factors influencing sex differentiation. We identified 110,870 full-length transcripts and obtained 100,362 (90.52%) transcript and annotation information. Then we identified 49,448 differentially expressed genes (DEGs) and 3,070 differentially accumulated metabolites (DAMs) in female, male, and monoecious leaf samples. The co-enrichment analysis indicated that sexual differentiation was regulated by glutathione metabolism, photosynthesis, plant hormone biosynthesis, catabolism, and signaling. The identification of DEGs and DAMs that participate in glutathione metabolism, photosynthesis, abscisic acid (ABA), cytokinin (CTK), and gibberellin (GA) biosynthesis, catabolism, and signaling has helped illuminate the roles of plant hormones in the sex differentiation of B. dactyloides. The full-length transcriptomic data will facilitate additional studies on functional genes. Integration of transcriptomic and metabolomic data advances knowledge of the molecular mechanism of sex differentiation and provides information for B. dactyloides breeding programs.