Hao He, Lei Caiyan, Dong QiuLei, Shen Yalin, Chi Jianting, Ye Hechun, Wang Hong
University of Chinese Academy of Sciences, Beijing, 100049, China.
Appl Biochem Biotechnol. 2014 Aug;173(8):2198-210. doi: 10.1007/s12010-014-1025-9. Epub 2014 Jun 29.
The shikonin derivatives, accumulated in the roots of Arnebia euchroma (Boraginaceae), showed antibacterial, anti-inflammatory, and anti-tumor activities. To explore their possible biosynthesis regulation mechanism, this paper investigated the effects of exogenous methyl jasmonate (MJ) on the biosynthesis of shikonin derivatives in callus cultures of A. euchroma. The main results include: Under MJ treatment, the growth of A. euchroma callus cultures was not inhibited, but the expression level of both the genes involved in the biosynthesis of shikonin derivatives and their precursors and the genes responsible for intracellular localization of shikonin derivatives increased significantly in the Red Strain (shikonin derivatives high-producing strain). The quantitative analysis showed that six out of the seven naphthoquinone compounds under investigation increased their contents in the MJ-treated Red Strain, and in particular, the bioactive component acetylshikonin nearly doubled its content in the MJ-treated Red Strain. In addition, it was also observed that the metabolic profiling of naphthoquinone compounds changed significantly after MJ treatment, and the MJ-treated and MJ-untreated strains clearly formed distinct clusters in the score plot of PLS-DA. Our results provide some new insights into the regulation mechanism of the biosynthesis of shikonin derivatives and a possible way to increase the production of naphthoquinone compounds in A. euchroma callus cultures in the future.
紫草素衍生物积聚在新疆紫草（紫草科）的根部，具有抗菌、抗炎和抗肿瘤活性。为了探究其可能的生物合成调控机制，本文研究了外源茉莉酸甲酯（MJ）对新疆紫草愈伤组织培养物中紫草素衍生物生物合成的影响。主要结果如下：在MJ处理下，新疆紫草愈伤组织培养物的生长未受抑制，但在红色菌株（紫草素衍生物高产菌株）中，参与紫草素衍生物及其前体生物合成的基因以及负责紫草素衍生物细胞内定位的基因的表达水平均显著增加。定量分析表明，所研究的七种萘醌化合物中有六种在MJ处理的红色菌株中的含量增加，特别是生物活性成分乙酰紫草素在MJ处理的红色菌株中的含量几乎增加了一倍。此外，还观察到MJ处理后萘醌化合物的代谢谱发生了显著变化，在PLS-DA得分图中，MJ处理和未处理的菌株明显形成了不同的聚类。我们的结果为紫草素衍生物生物合成的调控机制提供了一些新的见解，并为未来提高新疆紫草愈伤组织培养物中萘醌化合物的产量提供了一种可能的方法。
