# Multi-Omics and Functional Insights into Triterpenoid Biosynthesis Pathways in Neopicrorhiza scrophulariiflora (Pennell) D.Y.Hong

## TL;DR

This study explores how triterpenoids are made in a rare herb using multi-omics and functional analysis, identifying key genes and enzymes involved in the process.

## Contribution

The study identifies and functionally characterizes key genes, including a bifunctional enzyme, in triterpenoid biosynthesis in Neopicrorhiza scrophulariiflora.

## Key findings

- Eight upstream oxidosqualene cyclases were characterized in triterpenoid biosynthesis.
- NsOSC2 is a bifunctional enzyme that catalyzes the conversion of 2,3-oxidosqualene to β-amyrin and α-amyrin.
- A regeneration and genetic transformation system was established for N. scrophulariiflora.

## Abstract

Neopicrorhiza scrophulariiflora (Pennell) D.Y.Hong, an endangered perennial herb, is rich in triterpenes, iridoids, and phenolic compounds, which exhibit significant pharmacological effects. However, the molecular mechanisms of triterpenoid biosynthesis in N. scrophulariiflora remain unclear. Here, transcriptomic and metabolomic analyses were performed to investigate the triterpene content in different tissues and the expression patterns of key enzyme-encoding genes related to triterpenoid biosynthesis. We functionally characterized eight upstream oxidosqualene cyclases (OSCs) involved in triterpenoid biosynthesis, among which NsOSC2 is a bifunctional enzyme capable of catalyzing the conversion of 2,3-oxidosqualene to β-amyrin and α-amyrin. Additionally, an efficient regeneration system and a stable genetic transformation system were established for N. scrophulariiflora. These findings reveal key genes in triterpenoid biosynthesis, providing a theoretical foundation for the future production of key triterpenoids in N. scrophulariiflora through synthetic biology approaches.