入侵性森林杂草薇甘菊的倍半萜生物合成及调控的分子机制研究

Mikania micrantha H.B.Kunth is a alien forest invasive weed worldwide, and had led to the enormous damage to the forest ecological environment in China. The effort to discover the resource utilization of M. micrantha, will provide an effective and efficient way to control the spread of M. micrantha in a sustainable manner. The sesquiterpene compounds were secondary metabolites observed and enriched in M. micrantha, having bioactivities of both allelopathy during M. micrantha invasion process, and to inhibit the growth of pathogens, tumor cells and so on. The mechanism analysis of sesquiterpene biosynthesis and regulation in M. micrantha is helpful, on the one hand, to understand mechanisms of the M. micrantha invasion process, on the other hand, to provide molecular theoretical basis on the resource utilization of M. micrantha..The terpene synthases encoded by the TPS genes is the core component to catalyze the biosynthesis of sesquiterpene compound. In this study, we will identify TPS gene candidates encoding enzymes catalyzing the biosynthesis of sesquiterpene in the leaf of M. micrantha high expressed under the high CO2 concentration treatment with transcriptome analysis. Based on the available M. micrantha genomic library and pooling strategy, features of genome regions containing loci of TPS gene candidates will be characterized, and genes clusters potential involved in sesquiterpenes synthesis could also be explored in genome regions surrounding the TPS gene candidates. These TPS gene candidates as well as their promoters will be cloned, and then be transformed into , and and expressed in Arabidopsis. With inhibitory effect observation of Arabidopsis seed germination treated by transgenic plants extracts, the functions of TPS gene candidates will be verified.

薇甘菊是世界上危害严重的入侵性森林杂草，已对我国森林生态环境造成极大的危害。发掘薇甘菊的资源化潜力，是高效、持久开展薇甘菊防治工作的一条有效途径。倍半萜类化合物是薇甘菊体内含量较多的次生代谢产物，兼具薇甘菊入侵过程中的化感活性，及对病原菌、肿瘤细胞等的抑制活性。开展薇甘菊倍半萜合成及调控的分子机制研究，一方面有助于对薇甘菊入侵机制的分子解析；另一方面可为薇甘菊的资源化利用提供理论基础。.TPS基因编码的萜烯合酶是倍半萜合成途径的核心催化组件。本研究拟通过转录组手段，筛选出高CO2浓度下表达的薇甘菊倍半萜合成候选TPS基因。基于已构建的薇甘菊基因组文库和混池筛选策略，解析候选TPS基因所在的基因组区段特征，并发掘可能的倍半萜类合成功能基因簇。克隆候选TPS基因及启动子，转化至拟南芥植株中表达。通过观察转基因植株提取液对拟南芥种子萌发的抑制效应，验证薇甘菊倍半萜合成候选TPS基因的生物功能。