Figure 6.

Modular analysis of terpenoid-associated genes on the basis of WGCNA and γ-terpinene synthase-encoding gene expression analysis.

(A) The heatmap shows the relatedness of terpenoids with all coexpression modules identified in WGCNA.

(B) Modular organization analysis of terpenoid-related gene expression in thyme. Module–terpenoid correlations and corresponding p values (in parenthesis). The left panel shows 17 modules. The right panel is a color scale for module trait correlation from −1 to 1.

(C) Phylogenetic tree of the TPS-encoding genes (DEGs) in thyme and other species. TvTPS1, TvTPS2, TcTPS2.1, TcTPS2.2, OvTPS2.1, and OvTPS2.2 (orange color) are γ-terpinene synthase-encoding genes in thyme and oregano (Lamiaceae).

(D) Heterologous expression of TqTPS1 in Escherichia coli via in vitro enzyme assay. WGCNA, weighted gene coexpression network analysis.