# Molecular insights into Valencene synthase (SgTPS-V) and its role in sesquiterpenoid biosynthesis

## TL;DR

This paper identifies and characterizes a Valencene synthase gene in Salvia guaranitica, revealing its role in producing sesquiterpenes.

## Contribution

The study provides the first molecular characterization of Valencene synthase in Salvia guaranitica and its function in sesquiterpene biosynthesis.

## Key findings

- SgTPS-V was identified as a Valencene synthase in Salvia guaranitica based on in silico and in vitro analyses.
- Overexpression of SgTPS-V in Arabidopsis increased flowering and altered chemical profiles.
- The enzyme catalyzes the production of Valencene and related sesquiterpenes from FPP.

## Abstract

Salvia species produce a diverse array of terpenoids, particularly monoterpenes and sesquiterpenes, with applications in medicine, perfumery, and industry. However, the genes involved in sesquiterpene biosynthesis in Salvia guaranitica remain poorly characterized.

This study centers on the characterization of the Valencene synthase SgTPS-V from S. guaranitica. In silico analyses of SgTPS-V revealed conserved domains and motifs characteristic of terpene synthases, including DDxxxD, RWW, RxR, and NSE/DTE, and the phylogenetic tree placed it within the TPS-a subfamily, which encodes mono- and sesquiterpene synthases. Overexpression of SgTPS-V in Arabidopsis thaliana resulted in enhanced flowering relative to the wild-type. Also, comparing the chemical profiles of the transgenic Arabidopsis plants to wild-types indicated that SgTPS-V catalyzes the synthesis of Valencene, (-)-Valencene, (-)-Ledol, Viridiflorine and Valencene (isomer I), suggesting its role in sesquiterpene biosynthesis. Moreover, in vitro enzyme assay analysis for recombinant SgTPS-V protein showed that SgTPS-V had the capacity to convert FPP to considerable amount of Valencene and other amounts of sesquiterpenes. And based on results the major product for SgTPS-V was designated as a Valencene synthase.

These results provide light on the molecular basis of sesquiterpene production in S. guaranitica and pave the way for the discovery of other terpene synthase genes in this species.

The online version contains supplementary material available at 10.1186/s12870-026-08095-8.

Molecular cloning and characterization of Valencene synthase gene from S. guaranitica.

Putative tissue expression pattern of SgTPS-V gene under different tissues.

Putative conserved domains and motifs characteristic of SgTPS-V gene.

The online version contains supplementary material available at 10.1186/s12870-026-08095-8.