In Silico Genome-Wide Mining and Analysis of Terpene Synthase Gene Family in Hevea Brasiliensis

Terpene synthases (TPSs) catalyze terpenoid synthesis and affect the intracellular isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) concentration. In this study, we mined the in silico genome-wide TPS genes of Hevea brasiliensis and identified 47 full-length TPS genes. They had DDXXD, DXDD, NSE/DTE, RR(X)8 W, EA(X)W, and other conserved motifs. The phylogenetic tree analysis revealed that the TPSs of H.brasiliensis (HbTPSs) were divided into five subfamilies, TPS-a, TPS-b, TPS-c, TPS-e/f, and TPS-g. HbTPSs were predicted to have functions in the cellular components, molecular functions, and biological processes. HbTPSs were involved in seven pathways, which were K14173, K14175, K15803, K04120, K04121, K17982, and K12742 in the secondary metabolite pathway prediction. Three-dimensional structures of HbTPSs of 7 pathways were predicted, and DDXXD, NSE/DTE, and EA(X)W conserved motifs near the binding sites were found. Cis-acting elements analysis showed that they had more cis-acting elements related to phytohormone responsiveness, which indicated that terpenoid biosynthesis might be related to phytohormone regulation. RNA-Seq analysis showed that different HbTPSs were expressed differentially in different tissues. This study's results help reveal the role of HbTPSs and their molecular mechanism and help resolve the regulatory mechanism of terpenoid biosynthesis in H.brasiliensis.

Automated summary

In this study, 47 full-length HbTPS genes were identified in the Hevea brasiliensis genome, and they were divided into five subfamilies based on phylogenetic analysis. HbTPSs were found to participate in cellular components, molecular functions, and biological processes, as well as seven secondary metabolite pathways. They may be regulated by phytohormones, as suggested by the presence of cis-acting elements. RNA-Seq analysis revealed tissue-specific expression patterns of different HbTPSs. These findings contribute to understanding the role and molecular mechanism of HbTPSs and the regulation of terpenoid biosynthesis in H.brasiliensis.