Study on content of terpenoid indole alkaloids and transcriptional differences for covalent orca3/g10h in double-gene transgenic hairy roots of Catharanthus roseus / 中草药

ABSTRACT

Objective: In order to improve the content of terpenoid indole alkaloids (TIAs), orca3/g10h genes were introduced to the hairy roots in Catharanthus roseus. Methods: Bivalent expression vector CAMBIA1304+ +orca3 + g10h was constructed and introduced into Agrobacterium rhizogenes strain and transformed into C. roseus to obtain transgenic hairy roots. RT-qPCR was used to study the transcriptional differences of relative genes referred to the biosynthesis pathway of TIAs. Then HPLC was used to study TIAs content in the transgenic hairy roots of C. roseus, including vinblastine, vincristine, and ajmalicine. Results: The transcriptional level of genes that linked to biosynthesis of TIAs in the transgenic hairy roots of C. roseus, asα, ggpps, g10h, str, tdc, cpr, sgd, and dat, were all expressed higher than those of the nontransgenic roots. HPLC results showed that modified hairy root of C. roseus owned more total TIAs production, 58.23 mg/g, the number was larger than that of common roots in C. roseus as many as 27.5 times. On the other hand, the average content of vinblastine and vincristine was also more than the common roots in C. roseus. Among them, vinblastine content was the most. The number of production got 51.30 mg/g, which was as many as 197.3 times of the common root of C. roseus. Conclusion: Orca3/g10h double-gene transgenic hairy root of C. roseus can increase TIAs content efficiently.