Synergistic effect on biosynthesis of Panax notoginseng saponins by overexpressing a transcription factor PnbHLH and RNA interference of cycloartenol synthase gene.
10.19540/j.cnki.cjcmm.20201011.101
- Author:
Li JIANG
1
;
Yi-Lin YU
1
;
Min JIANG
1
;
Xiu-Ming CUI
1
;
Di-Qiu LIU
1
;
Feng GE
1
Author Information
1. Key Laboratory of Panax notoginseng Resources Sustainable Development and Utilization, Faculty of Life Science and Technology, Kunming University of Science and Technology Kunming 650500, China.
- Publication Type:Journal Article
- Keywords:
Panax;
Panax notoginseng;
RNA interference;
saponin;
transcription factor bHLH
- MeSH:
Intramolecular Transferases;
Panax notoginseng;
RNA Interference;
Saponins;
Transcription Factors/genetics*
- From:
China Journal of Chinese Materia Medica
2021;46(1):94-102
- CountryChina
- Language:Chinese
-
Abstract:
This study cloned the transcription factor gene PnbHLH which held an open reading frame of 966 bp encoding 321 amino acids. This study constructed the overexpression vector of transcription factor PnbHLH of Panax notoginseng. The combination of PnbHLH overexpression and RNAi of the key enzyme gene PnCAS involved in the phytosterol biosynthesis was achieved in P. notoginseng cells, thus exploring the biosynthetic regulation of P. notoginseng saponins(PNS) by the synergistic effect of PnbHLH overexpression and PnCAS RNAi. The results showed that the PnbHLH transcription factor interacted with the promoters of key enzyme genes PnDS, PnSS and PnSE in the biosynthetic pathway of PNS, and then regulated the expression levels of key enzyme genes and affected the biosynthesis of saponins indirectly. Further study indicated that the synergistic effect of PnbHLH overexpression and PnCAS RNAi was a more effective approach to regulate the biosynthesis of saponins. Compared with the wild type and PnCAS RNAi cells of P. notoginseng, the contents of total saponins and monomeric saponins(Rd, Rb_1, Re, Rg_1 and R_1) were increased to some extent in the cell lines of PnbHLH overexpression and PnCAS RNAi. This indicated that the two ways of forward regulation and reverse regulation of saponin biosynthesis showed superposition effect. This study explored a more rational and efficient regulation strategy of PNS biosynthesis based on the advantages of multi-point regulation of transcription factors as well as the down-regulation of by-product synthesis of saponins.
