[Cloning and functional verification of farnesyl pyrophosphate synthase gene(AvFPS) from Aconitum vilmorinianum]

Aconitum vilmorinianum is an authentic and superior medicinal herbal in Yunnan, which is rich in yunaconitine and other diterpene alkaloids. Diterpene alkaloids are its main active components. Farnesyl pyrophosphate synthase(FPS) is a key enzyme in the terpene biosynthetic pathway and plays an important role in diterpene alkaloid biosynthesis. Functional studies of FPS help to reveal the molecular mechanism of diterpene alkaloid biosynthesis. In this study, one FPS gene(AvFPS) was selected based on the transcriptome data of A. vilmorinianum. Its full-length sequence was cloned, and bioinformatic analysis, functional verification, and gene expression analysis were performed. The open reading frame(ORF) of AvFPS was 1 056 bp, encoding 351 amino acids. Its molecular weight was 41 kDa. AvFPS had two typical conserved functional domains of isopentenyl transferase, " DDIMD" and " DDYXD". The recombinant protein of AvFPS was expressed in Escherichia coli, and purified recombinant protein was used for in vitro enzymatic reaction. The results revealed that AvFPS was able to catalyze the synthesis of farnesyl pyrophosphate(FPP). The results of qRT-PCR analysis showed that AvFPS was expressed in the roots, stems, leaves, and flowers of A. vilmorinianum, with the highest expression level in the roots. The expression level of AvFPS was significantly up-regulated by MeJA induction. This study clarified the catalytic function of AvFPS, revealed the expression pattern of AvFPS in different tissue, as well as at different time induced by MeJA, and provided a reference for a deeper understanding of the function of FPS in the biosynthesis of diterpenoid components.