Shi Min, Zhou Wei, Zhang Jianlin, Huang Shengxiong, Wang Huizhong, Kai Guoyin
Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, Hangzhou Normal University, Hangzhou 310018, People's Republic of China.
Institute of Plant Biotechnology, Development Center of Plant Germplasm Resources, College of Life and Environment Sciences, Shanghai Normal University, Shanghai 200234, People's Republic of China.
Sci Rep. 2016 Feb 15;6:20919. doi: 10.1038/srep20919.
Jasmonic acid (JA) is an important plant hormone involved in regulation of many aspects of plant growth and development including secondary metabolism and JASMONATE ZIM-DOMAIN (JAZ) proteins are key components in JA signal processes. In this study, two new JAZ genes named SmJAZ3 and SmJAZ9 were cloned from S. miltiorrhiza hairy roots and characterized. Expression profiles under methyl jasmonate (MJ) treatment revealed that SmJAZ3 and SmJAZ9 were both MJ-responsive. Subcellular localization assay showed that SmJAZ3 was located in nucleus while SmJAZ9 was preferentially in nucleus. Expression of SmJAZ3 and SmJAZ9 in S. miltiorrhiza hairy roots differently affected the production of tanshinone. Over-expression of SmJAZ3 or SmJAZ9 in hairy roots produced lower level of tanshinone compared with the control, tanshinone production was as low as 0.077 mg/g DW in line SmJAZ3-3 and 0.266 mg/g DW in line SmJAZ9-22. Whereas, down-regulation of SmJAZs enhanced tanshione production, the content of tanshinone increased to 2.48 fold in anti-SmJAZ3-3 line, and 1.35-fold in anti-SmJAZ9-23 line. Our work indicated that SmJAZ3 and SmJAZ9 are involved in regulation of tanshinone biosynthesis and act as repressive transcriptional regulators in the JA signaling pathway, which paves the way to further dissect molecular mechanism in details in the future.
茉莉酸（JA）是一种重要的植物激素，参与调控植物生长发育的多个方面，包括次生代谢。茉莉酸锌结构域（JAZ）蛋白是JA信号传导过程中的关键组分。本研究从丹参毛状根中克隆并鉴定了两个新的JAZ基因，命名为SmJAZ3和SmJAZ9。茉莉酸甲酯（MJ）处理下的表达谱显示，SmJAZ3和SmJAZ9均对MJ有响应。亚细胞定位分析表明，SmJAZ3定位于细胞核，而SmJAZ9优先定位于细胞核。SmJAZ3和SmJAZ9在丹参毛状根中的表达对丹参酮的产生有不同影响。与对照相比，毛状根中SmJAZ3或SmJAZ9的过表达导致丹参酮水平降低，在SmJAZ3 - 3株系中丹参酮产量低至0.077 mg/g干重，在SmJAZ9 - 22株系中为0.266 mg/g干重。然而，SmJAZs的下调提高了丹参酮产量，在抗SmJAZ3 - 3株系中丹参酮含量增加到2.48倍，在抗SmJAZ9 - 23株系中增加到1.35倍。我们的工作表明，SmJAZ3和SmJAZ9参与丹参酮生物合成的调控，并在JA信号通路中作为抑制性转录调节因子，为未来进一步详细剖析分子机制铺平了道路。
