长春花生物碱生物合成受钾元素调控的代谢和分子基础

The tropical plant Madagascar periwinkle Catharanthus roseus produces wide arrays of pharmaceutically used terpene indole alkaloids (TIAs). Recently, plant secondary metabolsim and stress response were reported to be regulated in a complex and unclear transcriptional network induced by potassium nutrition. Our preliminary observation showed that potassium actively influenced TIA metabolism in seedlings. In addition, ethylene and redox state were tightly related to this induciton process. However, the detailed metabolic and molecular mechanisms involved in this process remain to be investigated. Focusing on this question, we are attempted to unravel the effects of potassium on growth, TIAs accumulaitons, ethylene response, redox state at the metabolic and molecular levels. At the same time, the organ-specific gene expression properties encoding series of key enzymes in TIAs biosynthesis, ethylene synthesis and signaling process, were assayed based on the transcriptomic data obtained recently. Transcriptomic data of C. roseus offering ample sequence resources for providing better insights into gene diversity to accelerate genomic studies in Catharanthus. Our research will provide an insight into physiological and molecular mechanisms of TIAs metabolism regulation affected by potassium. Ultimately, an innovative regulatory network including potassium, ethylene and ROS is engaged to be established regarding TIAs regulation at the metabolic and molecular levels.

药用植物长春花（Catharanthus roseus）含有种类丰富的萜类吲哚生物碱（terpene indole alkaloids, TIAs），大多具有药用活性。近年来研究表明，钾营养与植物次生代谢合成调控密切相关。我们前期研究表明，钾营养积极影响长春花TIAs积累，并且其调控过程与乙烯响应和氧化调控密切相关，但其代谢和分子调控机制目前还不清楚。针对该问题，本项目拟从代谢、分子、转录调控等水平，研究揭示钾营养对TIAs积累、TIAs合成途径基因表达、乙烯响应、氧化动态的影响机制；同时利用项目组已得到的长春花转录组分析结果挖掘长春花响应钾元素的差异表达基因，阐明乙烯和氧化信号分子分别在介导钾元素诱导长春碱合成过程中的分子调控作用。

药用植物长春花（Catharanthus roseus）含有种类大量的萜类吲哚生物碱（terpene indole alkaloids, TIAs），大多具有药用活性。我们前期研究显示，钾营养与植物次生代谢合成调控密切相关。本项目拟从代谢、分子、转录调控等水平，研究揭示钾营养对TIAs积累、TIAs合成途径基因表达影响；同时通过转录组，研究乙烯和氧化信号分子分别在介导钾元素诱导长春花生物碱合成过程中的调控作用。在项目执行过程中，首先建立了超高液相色谱（UPLC）同时检测长春花生物碱的高效方法，并从代谢和生理水平上研究了钾元素对长春花幼苗多种TIAs积累以及乙烯响应和氧化还原状态的影响，分析阐述了乙烯和氧化信号参与钾离子调控长春碱合成和积累的初步机制；最后利用转录组测序，研究了长春花受钾元素调控的转录谱，发现乙烯响应因子ERF和EIN3受到钾元素的积极调控，且其转录水平与TIAs合成酶基因表达水平密切正相关，初步证明乙烯积极参与了钾调控TIA合成。研究结果已发表5篇项目标注的SCI收录学术论文。