二氧化碳浓度升高对茶树类黄酮合成代谢的影响及其调控机制

Flavonoids are considered as the most important bioactive compounds for tea quality and its health benefits; however, the synthetic metabolism of flavonoids is sensitive to changes in the environmental factors. At present, elevated CO2 concentration is one of the most important global concerns due to its potential to cause ecological changes in the face of climate change. However, the effect of elevated CO2 concentration on the metabolism of flavonoids in tea plant is still unclear . Our previous studies showed that elevated CO2 improved catechins synthesis, which are the components of flavonoids in tea plant, and thus affect the quality of tea. Hence, this project intends to investigate effect and regulation mechanism of elevated CO2 on flavonoids synthesis and metabolism using tea plant as material. Tea seedling will be treated in controlled environment with different CO2 concentrations to elucidate its effect on flavonoids biosynthesis metabolism by transcriptome and metabolome analyses using RNA-seq and UPLC/Q-TOF-MS technology. Chemical-genetics approaches that alter the levels of endogenous hormones (SA, ETH) and signal substances (H2O2, NO) in tea plant will be used to understand the involvement of those regulatory factors and the corss-talk of them in elevated CO2-mediated flavonoids synthesis and metabolism. This study is expected to reveal the effects of elevated CO2 concentration on the quality of tea and provide a comprehensive picture for the regulatory mechanisms of flavonoids synthesis.

类黄酮是茶叶品质和保健功能的首要成分，其合成代谢容易受环境影响。CO2浓度升高是当前全球范围内最重要的生态变化之一，但CO2浓度升高对茶树类黄酮代谢的影响和调控机制尚不清楚。申请人前期研究发现CO2浓度升高能够显著提高茶树类黄酮物质中儿茶素的含量，进而影响茶叶品质。项目组拟以茶树为材料，通过人工控制CO2浓度，利用RNA-seq和UPLC-Q-TOF/MS技术对不同浓度CO2处理的茶树植株进行转录组和代谢组分析，研究CO2浓度升高对茶树类黄酮合成代谢的影响；同时，利用化学遗传手段，改变不同CO2浓度环境下茶树植株中SA、ETH、H2O2、NO等信号物质水平，研究茶树类黄酮合成代谢响应，筛选CO2浓度升高环境下茶树类黄酮合成代谢的调控因子，并进一步探讨调控因子间的互作关系。本项目的完成将有助于揭示CO2浓度升高对茶叶品质的影响，并为深入解析茶树类黄酮合成调控提供借鉴。

类黄酮是茶叶品质和保健功能的首要成分，其合成代谢容易受环境影响。CO2浓度升高是当前全球范围内最重要的生态变化之一，但CO2浓度升高对茶树类黄酮代谢的影响和调控机制尚不清楚。项目申请人以茶树为材料，通过人工控制CO2浓度，利用RNA-seq和UPLC-Q-TOF/MS技术对不同浓度CO2处理的茶树植株进行转录组和代谢组分析，研究CO2浓度升高对茶树类黄酮合成代谢的影响；同时，利用化学遗传手段，通过改变不同CO2浓度环境下茶树植株中植物激素水杨酸（SA）和次级信号物质一氧化氮（NO）的水平，并进一步探讨了SA和NO的互作关系在CO2浓度升高调控茶树类黄酮合成代谢中的调控机理。研究发现，CO2浓度升高会显著提高茶树叶片中类黄酮物质的含量，并且SA和NO的含量也随之提高。进一步的研究表明，SA和NO在CO2诱导的类黄酮物质的生物合成过程中是非常重要的，并且SA作用于NO的上游发挥调控作用。本项目的完成有助于揭示CO2浓度升高对茶叶品质的影响，并为深入解析茶树类黄酮合成调控提供借鉴。