Identification and Expression Analysis of the Terpenoid Synthase Gene Family in Dendrobium nobile

Terpenoid synthase (TPS) is a crucial enzyme catalyzing terpenoid synthesis in plants. However, the TPS gene family and its expression patterns in different growth stages of Dendrobium nobile remain unexplored. This study aims to systematically identify and analyze TPS family members using whole genome sequencing. Results revealed the identification of 50 TPS gene family members, with predicted molecular weights ranging from 14,531 to 162,002 Da. Subfamilies TPS-a, TPS-b, TPS-c, and TPS-e/f were detected in Dendrobium nobile. Furthermore, UPLC-Q/TOF-MS technology was utilized to analyze sesquiterpenoid compounds in the stems of 1-year-old and 3-year-old Dendrobium nobile. The content of sesquiterpenoid compounds, including dendroxine and dendronobiloside A, increased with plant age. That increase in content can be attributed to the upregulation of sesquiterpene synthase, a hypothesis validated through transcriptome sequencing, qRT-PCR, and molecular docking. The results over time suggest that sesquiterpenoid compounds may play a role in regulating sesquiterpene synthesis in Dendrobium nobile in conjunction with TPS genes. We promote the development of Dendrobium nobile into the food field. It is conducive to the rational development and utilization of Dendrobium nobile.