Unveiling Monoterpene Biosynthesis in via Functional Characterization.

is a monotypic species, and its terpenoid-rich property has been reported in recent years. To uncover monoterpene biosynthesis in , this study used transcriptome mining to identify candidates with tentative monoterpene synthase activity. Along with the phylogenetic analysis and in vitro assay, two geraniol synthases (TPS13 and TPS14), a linalool synthase (TPS15), and a β-pinene synthase (TPS16), were functionally characterized. Via the comparison of catalytic residues, the Cys/Ser at region 1 might be crucial in determining the formation of α-pinene or β-pinene. In addition, the Cupressaceae monoterpene synthases were phylogenetically clustered together; they are unique and different from those of published conifer species. In summary, this study aimed to uncover the ambiguous monoterpenoid network in , which would expand the landscape of monoterpene biosynthesis in Cupressaceae species.