# Unveiling the Synergistic Effect of Salicylic Acid on Triterpenoid Biosynthesis in Athelia termitophila: Elucidating the Molecular Underpinnings

## TL;DR

This study shows how salicylic acid boosts triterpene production in a fungus and reveals the genes involved in the process.

## Contribution

The study identifies key genes and their expression patterns in triterpene biosynthesis using salicylic acid treatment in Athelia termitophila.

## Key findings

- Salicylic acid at 200 μmol/L increased triterpene yield by 21.87% in Athelia termitophila.
- Four key genes (AACT, SE, PMK, MVD) were identified as important for triterpene synthesis.
- Cluster analysis revealed new gene expression patterns during triterpene production.

## Abstract

This study investigates the dual role of salicylic acid (SA) in enhancing the production of triterpenes and elucidates its molecular regulatory mechanisms in the fungus Athelia termitophila (TMB), a rich source of bioactive triterpenoids vital to the cosmetics and pharmaceutical industries. Our innovative approach involves the strategic application of SA during the mycelial growth phase, leading to a remarkable 21.87% increase in triterpene yield under optimized conditions of 200 μmol/L SA over 9 days. Pioneering in its methodology, our research employs Spearman correlation analysis to dissect the intricate relationship between triterpene content and gene expression within the mevalonate (MVA) pathway of A. termitophila. This analysis has identified four key genes—Acetyl-Coa Acetyltransferase (AACT), Squalene Epoxidase (SE), Phosphomevalonate Kinase (PMK), and Mevalonate Diphosphate Decarboxylase (MVD)—that are important for triterpene synthesis, providing new insights into the biosynthetic capabilities of A. termitophila. Furthermore, our application of cluster analysis has unveiled unprecedented expression patterns among critical genes, at specific growth intervals. This novel insight into the temporal dynamics of gene transcription during triterpene synthesis provides a comprehensive view of the biosynthetic process, setting the stage for targeted enhancement of triterpene production in A. termitophila. This investigation not only highlights TMB’s potential as a biotechnological source of triterpenes but also provides critical insights into the underlying molecular pathways responsible for triterpene synthesis.