基于代谢组学研究的东南景天锌超积累相关代谢通路分析

Zinc is an essential microelement for creature and human being, but Zn malnutrition or Zn deficiency in human population is still high. Hence, deep understanding the mechanisms of Zn hyperaccumulation in plants is of great scientific significance for Zn biofortification and the production of healthy agricultural products. The proposed research project is aimed to understand the major vital metabolic pathways associated with Zn hyperaccumulation in the hyperaccumulator Sedum alfredii H by means of various advanced-omics analysis techniques and bases of our past research achievements. The Metabolome Profiling will be applied to explicate the importance and roles of the vital enzymes, vital metabolites in Zn accumulation for the carbon and the sulfur metabolic pathways. Besides, the Metabolic Flux Analysis (MFA) will be employed to analyze the key metabolic pathways and build up the metabolic pathway model of S. alfredii Hance, in order to elucidate the regulation relationship between key metabolic pathway and Zn homeostasis network. This research is the first to study Zn hyperaccumulation mechanism of S. alfredii Hance based on metabolic pathway. The output results will provide the theoretical foundation for further in-depth study on molecular mechanism of Zn hyperaccumulation of S. alfredii H, and provide scientific bases for regulating Zn biofortification in crop plants.

锌是生物与人体营养生存必需微量元素，但低锌贫营养人群仍很大，深入研究植物锌超积累关键过程机理对锌营养强化与健康农产品生产具重大科学意义。本项目在前期大量研究的基础上，通过代谢组学分析明确东南景天关键代谢通路，并通过具体分析代谢通路的关键酶、关键代谢物阐明关键代谢通路所起的重要作用，进而应用稳态代谢通量（MFA）分析方法研究东南景天关键代谢通路与锌稳态网络调控关系，并构建代谢模型。本项目首次从代谢通路的角度阐明东南景天的锌超积累过程及机理。研究结果可为东南景天锌超积累分子机制的研究提供理论依据，也为农作物锌生物强化调控提供科学依据。

锌是生物与人体营养生存必需微量元素，但低锌贫营养人群仍很大，深入研究植物锌超积累关键过程机理对锌营养强化与健康农产品生产具重大科学意义。本项目在前期大量研究的基础上，通过代谢组学分析明确东南景天关键代谢通路，本项目在研期间，初步探明了超积累东南景天在24小时和7天锌处理条件下的元素、代谢、转录和蛋白整体响应。确定了碳代谢、硫代谢和氨基酸代谢等三类关键代谢通路。绘制了硫代谢和氨基酸代谢调控网络。在完成预定研究任务的同时，还进一步结合分子生物学的研究方法，对超积累东南景天NAS和NRAMP家族基因的功能进行了研究，为今后进一步从分子水平上深入提示植物锌超积累的分子机制打下基础。初步阐明了超积累生态型东南景天体内对锌快速吸收和超量积累的关键代谢机制。本项目首次从代谢通路的角度阐明东南景天的锌超积累过程及机理。研究结果可为东南景天锌超积累分子机制的研究提供理论依据，也为农作物锌生物强化调控提供科学依据。