PnMYB4 negatively modulates saponin biosynthesis in Panax notoginseng through interplay with PnMYB1  

作　　者：Jinhui Man Yue Shi Yuying Huang Xiaoqin Zhang Xin Wang Shanhu Liu Gaojie He Kelu An Dongran Han Xiaohui Wang Shengli Wei 

机构地区：[1]School of Chinese Materia Medica,Beijing University of Chinese Medicine,Beijing 102488,China [2]School of Life and Science,Beijing University of Chinese Medicine,Beijing 102488,China [3]Modern Research Center for Traditional Chinese Medicine,Beijing Institute of Traditional Chinese Medicine,Beijing University of Chinese Medicine,Beijing 102488,China

出　　处：《Horticulture Research》2023年第8期203-215,共13页园艺研究（英文）

基　　金：This study was supported by Beijing Science and Technology Planning Project(Z201100005420005,China).

摘　　要：Saponins are the main triterpenoid ingredients from Panax notoginseng,a well-known Chinese medicine,and are important sources for producing drugs to prevent and treat cerebrovascular and cardiovascular diseases.However,the transcriptional regulatory network of saponin biosynthesis in P.notoginseng is largely unknown.In the present study we demonstrated that one R2R3-MYB transcription factor,designated PnMYB4,acts as a repressor of saponin accumulation.Suppression of PnMYB4 in P.notoginseng calli significantly increased the saponin content and the expression level of saponin biosynthetic genes.PnMYB4 directly bound to the promoters of key saponin biosynthetic genes,including PnSS,PnSE,and PnDS,to repress saponin accumulation.PnMYB4 and the activator PnMYB1 could inter-acted with PnbHLH,which is a positive regulator of saponin biosynthesis,to modulate the biosynthesis of saponin.PnMYB4 competed with PnMYB1 for binding to PnbHLH,repressing activation of the promoters of saponin structural genes induced by the PnMYB1-PnbHLH complex.Our study reveals that a complex regulatory module of saponin biosynthesis is associated with positive and negative MYB transcriptional regulators and provides a theoretical basis for improving the content of saponins and efficacy of P.notoginseng.

关 键 词：COMPLEX ACTIVATION SAPONIN 

分 类 号：Q94[生物学—植物学]