不同发育阶段金银花活性成分特异性合成的系统生物学研究

Lonicera japonica Thunb. is a herbal medicine that with significant antiviral, antimicrobial and antioxidant activities. Caffeoyl guinic acids and iridoid glycosides are the main active ingredients in L. japonica. The development of L. japonica flower was divided into seven phases, including buds, sanqing, erbai, dabai, silver flower, golden flower and dead flower. Previous studies indicated that the content of the bioactive components in different flowering phases were distinctly different. Up to date, the correlations between active components and flowering phases has seldom been investigated with system biological approaches. Several key enzymes in the biosynthesis pathway of caffeoyl guinic acid and iridoid glycoside in L. japonica have been identified in our preliminary proteomic studies. To clarify the molecular mechanism for the activity differences in the flowering phases, system biological approaches, which integrate comparative transcriptomic, proteomic and metabolomic methods will be applied in this study. The study would uncover the major differential transcripts and proteins, which are crucial for the differences in the content of active components in L. japonica. While the metabolomic results directly illustrate the modifications on the bioactive metabolic profiles in the different flowering phases, and provide the molecular evidence for the best harvesting period. The system biology study on medicinal plants will provide detailed information for the biosynthesis of natural product, as well as the rational utilization of natural resources in the future.

金银花是常用天然药物，具有显著的抑菌、抗病毒和抗氧化活性。研究表明金银花发育的七个时期：幼蕾期、三青期、二白期、大白期、银花、金花期和凋花期，其主要活性成分咖啡酰奎宁酸和环烯醚萜含量差异显著，关于金银花活性成分与花期相关性的系统生物学研究未见报道；前期我们应用差异蛋白质组学找到了数个咖啡酰奎宁酸和环烯醚萜生物合成途径的关键酶。为了阐明金银花不同花期活性成分差异的分子机理，本研究拟应用系统生物学研究方法，综合代谢组、药效学、转录组和蛋白质组研究，对金银花不同发育阶段综合分析，找出不同花期金银花活性成分的代谢变化规律，挖掘不同花期金银花活性成分生物合成的差异蛋白和差异表达基因，阐明金银花发育过程中的活性成分变化规律，为合理选择金银花的采摘时期提供理论依据，也为天然产物生物合成机理的研究提供有益探索。系统生物学在药用植物有效成分形成机理方面的发展与应用，对于合理开发利用药用植物资源具有重要意义。

金银花是常用天然药物，具有显著的抑菌、抗病毒和抗氧化活性。金银花发育时期其主要活性成分含量差异显著。本项目对金银花不同花期提取物中的简单苯丙素类、黄酮类、萜类和生物碱类等重要活性物质进行了初步定性，整合代谢组学、蛋白质组学和转录组学数据，构建了代谢物、基因及蛋白的动态网络互作图谱，对金银花全发育期进行了系统性分析。发现与光合作用、糖酵解、细胞壁发育和次生代谢相关的基因，蛋白质和代谢物的数量变化具有系统统一性，而糖酵解过程对次生代谢过程中的物质代谢发挥重要作用，糖酵解过程中Enolase 和PK酶催化合成的磷酸烯醇式丙酮酸和丙酮酸对下游次生代谢的合成发挥关键作用。对金银花五个花期的转录因子分析表明转录因子MYB12和MYB44可能在金银花不同花期可能对黄酮类化合物合成有调控作用而NAC与WRKY家族的转录因子可能联合多种激素调节及ROS活动调控金银花的衰老过程。以上研究不仅揭示了金银花花期重要活性物质积累的内在机制，而且对于指导金银花种植生产和科学选择性采收提供了专业理论指导。