植物新型萜类合成酶基因的功能和进化

Terpenoids is the largest class of secondary metabolites made by plant, they have important physiological and ecological functions as well as medicinal values. Terpene synthase(TPS) is the key enzyme for the biosynthesis of terpenoids, and it is hot that understanding the molecular basis of the vast diversification of TPS in plant. We investigated TPS in Selaginella moellendorfii species, which belongs to nonseed vascular in plant phylogeny. Except for the discovery of seed plant type of terpene synthase gene(pTPS), we firstly reported a novel type of terpene synthase gene(mTPS) in Selaginella moellendorfii species, which we designated as new TPS. Now it is unclear that what is the distribution of this type of mTPS. Four representative plant species including Anthoceros punctatus, Lycopodiastrum casuarinoides, Isoetes sinensis and Pteridium aquilinum var. latiusculum, were choosen in order to further understand the function and evolutionary origin of the mTPS. Firstly mTPS will be systematically predicted and validated by integrating data from known plant transcriptome and new data from this project. Then, methods including in vitro enzyme activity analysis, protein homologous modeling, point mutation and GC-MS analysis will be integrated to clarify the biochemical and biological function of mTPS. Finally, comparative genomics and molecular evolution methods will be also applied, so that the function and evolution of mTPS will be elucidated. The discovery of mTPS provides evidence for further exploring the diversification of physiological and biochemical function and possibility of multiple origin of TPS.

萜类是植物次生代谢物中种类最多的一类，它们具有重要的生理生态功能和药用价值。萜类合成酶（TPS）是萜类合成的关键酶，对其产物多样性的分子基础探究一直是植物次生代谢领域的研究热点。除发现植物型萜类合成酶（pTPS）基因外，我们在非种子维管植物江南卷柏中还首次报道了植物新型萜类合成酶（mTPS）基因，目前尚不清楚这类mTPS基因是否也存在于其它植物中。 为了深入理解mTPS基因的功能和进化起源，本项目以处于进化重要位置的角苔、藤石松、中华水韭和蕨等四种代表性植物为研究对象，首先整合现有的和自建的转录组数据，进行mTPS基因的生物信息学分析和实验鉴定。然后利用酶活分析，蛋白同源建模，点突变及气质联用等方法，进行mTPS基因的生化和生物学功能分析。最后通过比较基因组学和分子进化方法提出mTPS基因的功能和进化。mTPS基因的发现，为探索TPS的生理生化功能的多样性及进化起源的多元性提供了理论依据。

萜类是植物次生代谢物中种类最多的一类，它们具有重要的生理生态功能和药用价值。萜类合成酶（TPS）是萜类合成的关键酶，对其产物多样性的分子基础探究一直是植物次生代谢领域的研究热点。除发现植物型萜类合成酶（pTPS）基因外，我们在非种子维管植物江南卷柏中还首次报道了植物新型萜类合成酶（mTPS）基因。为了探究mTPS基因是否也存在于其它非种子植物中，本项目以处于进化重要位置的代表性苔藓和蕨类植物为研究对象，首先通过转录组数据的整合与分析，获得22个mTPS基因。然后对13个mTPS 基因（7个苔藓mTPS和6个蕨类mTPS）进行体外酶活、蛋白同源建模、点突变以及气质联用等分析，获得苔藓和蕨类植物中这13个mTPS的功能。最后通过比较基因组学和分子进化方法，提出mTPS 基因的进化起源。在此项目的基础上，申请到国家自然科学基金面上项目一项，发表SCI论文三篇，核心论文两篇，实现了预期的研究目标。