The GbbZIP41 transcription factor participates in terpene trilactones biosynthesis in Ginkgo biloba L.

Abstract

Terpene trilactones (TTLs) are important secondary metabolites in ginkgo tree (Ginkgo biloba), which play a crucial role in the treatment of human cardiovascular disease and prevention of thrombosis, and have been widely used in food, medicine and health products. However, there are few studies on the transcriptional modulation of TTLs biosynthesis and gene regulatory network of TTLs biosynthesis remains unclear. Here, we screened the transcription factor GbbZIP41 that may be involved in the biosynthesis of TTLs and verified its function by transgenic technology. The results showed that GbbZIP41 is a protein located in the nucleus and encodes 477 amino acids, which is highly expressed in G. biloba leaves. The analysis of total terpene content and GbbZIP41 gene expression in G. biloba leaves showed the opposite trend. In addition, the overexpression of GbbZIP41 gene in tobacco reduced the content of terpenoids and down-regulated the enzyme genes of MVA pathway and MEP pathway. Therefore, these results suggested that GbbZIP41 negatively regulates the biosynthesis of TTLs by inhibiting key enzyme genes in the TTLs synthesis pathway.