Cloning and expression of geranyl pyrophosphate synthase gene in Swertia mussotii / 中草药

ABSTRACT

Objective: To clone the geranyl pyrophosphate synthase gene from Swertia mussotii (SmGPPS), analyze the bioinformation of SmGPPS, and perform the gene expression. Methods: According to the SmGPPS gene sequence of transcriptome of S. mussotii, the specific primers were designed, the cDNA complete sequences was obtained by RT-PCR and the sequence was analyzed using bioinformatics. Prokaryotic expression vector pET-28a-SmGPPS was constructed and transformed into Escherichia coli BL-21 (DE3) for expression under 37℃ and induced by 1 mmol/L IPTG. The relative expression of gene SmGPPS in the leaf, stem, and flower of S. mussotii was also studied. Results: The results showed that SmGPPS cDNA complete sequences had a length of 1 119 bp encoding 372 amino acid residues. And the protein secondary and tertiary structures were analyzed and forecasted. The SmGPPS protein shared high identity with other GPPS proteins of plants. The SDS-PAGE results showed that the expressed proteins were consistent with the anticipated size. Relative RT-PCR analysis indicated that SmGPPS showed the highest transcript abundance in the leaf. Conclusion: This work will provide a foundation for further functional research of SmGPPS protein and increasing the product of iridoid compound by genetic engineering in S. mussotii.