Fig. 5

Terpenes biosynthesis in wintersweet. a Expression profiles of genes encoding enzymes possibly involved in monoterpene and sesquiterpene biosynthesis. Abbreviations for enzymes in each catalytic step are shown in bold. The gradient color for each gene represents the gene expression levels in three floral developmental stages (S1: bud stage; S4: full open flower stage; S5: senescence stage). Homologous genes are represented by equal colored horizontal stripes and are termed from top to bottom in Arabic numerical order. The full names of enzymes are listed in the Additional file 1: Table S18. The genes circled in green box were generated by WGD event. The non-boxed genes did not undergo this event. b Phylogeny of TPS proteins identified in wintersweet and 5 other sequenced plant genomes showing the subfamilies from a–g. c The expression of CpTPS genes in three different floral development stages. These genes were expressed in at least one of the three developmental stages. d The chromosomes with more than one CpTPS gene. The red diamonds represent the functionally characterized genes. The green diamonds represent the genes generated by tandem duplication events. The cure with arrow linked two duplicated genes. e Identification of enzymatic products after incubating recombinant CpTPSs proteins with geranyl diphosphate (GPP)/farnesyl diphosphate (FPP). The volatile terpenes were analyzed by GC-MS analysis and comparing with authentic standards. f Increased linalool biosynthesis in the CpTPS4-overexpressed tobacco compared with wild type (WT) and empty vector control (EV). Data represent the mean ± SDs of three biological replicates