Collaborative Research: A Systems Approach Toward Understanding the Diversification of Tropane and Granatane Alkaloid Biosynthesis

本项目的目的是利用比较的方法研究三个不同植物科中两种有机含氮化合物的合成途径，以发现新的基因，并测试这两种途径在每个家族中相互独立发展的假设。这些生物碱保护植物免受昆虫和其他害虫和病原体的侵害，并被人类用作调味料、香料、杀虫剂和药物。这项研究将为研究生和本科生提供基因组学、结构生物学、生物化学和分析化学的跨学科培训机会。此外，将透过伙伴实验室之间的交流，加强研究生培训，以促进跨学科技能的发展。正式的本科生交换将通过从德克萨斯理工大学或爱荷华州立大学招收女性和代表性不足的少数民族学生参加密歇根州立大学的本科生研究经验项目来完成。该项目还将直接与爱荷华州当地的一所社区学院合作，为社区学院的学生提供结构生物学的接触。Tropane和granatane生物碱包含一个核心双环结构，并且分散在不相关的植物科中。该研究项目将采用自上而下的转录组学和代谢组学相结合的方法，结合比较功能、生化和结构生物学的方法，阐明具有重要药用价值的莨菪碱和石榴烷生物碱的生物合成途径和机制。基因发现将发生在三个不同且重要的作物科：芸苔科、蓟科和红藓科，所得数据将与茄科中已建立的tropane途径进行比较。这种比较方法将被用来检验这样一种假设，即在不同物种的tropane生物合成途径中，新的生物催化活性是植物谱系中tropane生物碱系统独立出现的来源。此外，该研究还探讨了tropane生物碱代谢的不同组分被独立选择以构建新的代谢系统（例如granatane生物碱）的可能性。总的来说，这种方法将有助于增进对tropane和granatane生物碱生物合成的理解。此外，了解导致tropane和granatane生物碱的生物合成步骤对于这些药理活性化学物质的定量建模和代谢工程至关重要。

The goal of this project is to use comparative approaches to investigate the synthesis pathways of two organic, nitrogen containing compounds in three different plant families to discover new genes and test the hypothesis that these two pathways developed independently of one another in each family. These alkaloids defend plants against insects and other pests and pathogens, and are used by humans as flavourings, fragrances, pesticides and medicines. This research will provide multiple opportunities for interdisciplinary training in genomics, structural biology, biochemistry, and analytical chemistry to graduate and undergraduate students. Furthermore, graduate student training will be enhanced through implementation of exchanges between partner labs to facilitate the development of interdisciplinary skills. Formal undergraduate exchanges will be accomplished by the recruitment of female and underrepresented minority students from Texas Tech or Iowa State University into a Research Experience for Undergraduates (REU) Program at Michigan State University. The project also will work directly with a local Community College in Iowa to provide Community College students with exposure to structural biology.Tropane and granatane alkaloids contain a core bicyclic ring structure and appear scattered across unrelated plant families. The research project will utilize a top down approach of combined transcriptomics and metabolomics coupled with comparative functional, biochemical and structural biology based approaches to elucidate the pathways and mechanisms that underlie the biosynthesis of the pharmaceutically important tropane and granatane alkaloids. Gene discovery will occur in three distinct and important crop families: Brassicaceae, Lythraceae and Erythroxylaceae and the resulting data will be compared to an established tropane pathway in the Solanaceae. This comparative approach will be used to test the hypothesis that novel biocatalytic activities within the tropane biosynthetic pathways of distinct species are the source of the independent emergence of the tropane alkaloid system within the plant lineage. Additionally, the research explores the possibility that the different components of tropane alkaloid metabolism were independently co-opted to build new metabolic systems (e.g. granatane alkaloids). Overall, this approach will lead to enhanced understanding of tropane and granatane alkaloid biosynthesis. Moreover, knowledge of the biosynthetic steps leading to tropane and granatane alkaloids is crucial for quantitative modeling and metabolic engineering of these pharmacologically active chemicals.