Identification and Analysis of the TPS Gene Family in the Camellia sinensis Pan-Genome

Terpene synthases (TPSs) are key enzymes in plant terpenoid biosynthesis and play important roles in growth and environmental responses. Here, we analyzed 22 high-quality Camellia sinensis pan-genomes to characterize the TPS gene family at the pan-genome level. A total of 80 CsTPS genes were identified, including 12 core, 8 soft-core, 37 dispensable, and 23 private genes. Phylogenetic analysis classified these genes into five subfamilies, with TPS-b containing the highest number of core members. Duplication analysis showed that transposed duplication and whole-genome duplication were the main contributors to CsTPS family expansion. Several genes, including TPS36, TPS59, and TPS63, showed signals of positive selection (Ka/Ks > 1). Structural variant analysis indicated that variation affected gene structure and tran-scriptional regulation, particularly for TPS12, TPS43, and TPS27. Analysis of cis-regulatory elements and transcriptome data further indicated that CsTPS genes are associated with hormone-related pathways, development, and stress-responsive expression patterns. Overall, this study provides a pan-genomic overview of the evolutionary features and variation patterns of the TPS gene family in tea plants and offers a resource for future functional investigations.