基于茉莉酸甲酯诱导的丹参毛状根酚酸类成分次生代谢机制研究

目的:研究外源茉莉酸甲酯诱导后丹参毛状根中酚酸类有效成分形成的次生代谢分子机制.方法:用茉莉酸甲酯(MJ,100μmol·L-1)对丹参毛状根进行诱导实验,分别在0,6,12,24,36h收获材料,运用实时定量PCR对丹参中迷迭香酸次生代谢途径上的关键酶基因的mRNA表达水平进行检测.同时,采用LC-MS测定各个时间点毛状根材料中迷迭香酸(RA)、丹酚酸B(LAB)及咖啡酸(CA)的含量.结果与结论:外源性信号分子MJ作用于丹参毛状根,酚酸类成分迅速积累,表现为CA,RA均在诱导后24h达到最大值,LAB的含量36h后达到最高.其诱导机制可能与不同程度的激活RA合成中苯丙氨酸途径上关键酶基因PAL,4CL,C4H与酪氨酸途径中TAT,HPPR基因的表达有关,基因表达在时间呈现先后性,其中,4CL与PAL的贡献度较大.这为今后更深一步的研究丹参水溶性酚酸类成分的次生代谢途径机制提供了依据.

Research of mechanism of secondary metabolites of phenolic acids in Salvia miltiorrhiza hairy root induced by jasmonate

Objective: To study the mechanism of secondary metabolites of some phenolic acids in the hairy roots of Salvia miltiorrhiza induced by methyl jasmonate.Method: The hairy roots of S.miltiorrhiza were induced with methyl jasmonate(100 μmol·L-1) and collected at 0,12,24,36 h after treatment.Real-time quantitative PCR was used for detecting the mRNA expression level of the key enzyme genes on the secondary metabolites pathway of rosmarinic acid,while a LC-MS method was developed to determine the content of rosmarinic acid,caffeic acid and salvianolic acid B.Result and conclusion: The concentration of phenolic acids grew up and accumulated quickly in the hairy roots with exogenous signal molecule MJ induced,and it was showed that the content of CA and RA reached the maximum after 24 h and the content of LAB reached the maximum in 36 h by MJ induced.The induction mechanism may be activated with different levels of RA synthesis in PAL,4CL,C4H genes on the key enzyme phenylalanine pathway and TAT,HPPR genes on tyrosine pathway.The time of gene expression was different,among them,4CL and PAL genes were more important.In a word,the result can provide some basis data about the mechanism of secondary metabolites of phenolic acids for further research.