Limonoids and Quassinoids – Understanding and Harnessing Complex Triterpene Production and Transport in Plants

柠檬苦素和苦木素 - 了解和利用植物中复杂三萜的生产和运输

• 批准号: 426196231
• 负责人: Professor Dr. Jakob Franke
• 金额: --
• 依托单位: Zentrum für Biomolekulare Wirkstoffe (BMWZ)
• 依托单位国家: 德国
• 项目类别: Independent Junior Research Groups
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/426196231?language=en
• 关键词: Limonoids; Quassinoids; Understanding; Harnessing; Complex

Specialised metabolites from plants have been used by mankind for thousands of years, many of which are still essential medicines. Sometimes, though, specialised metabolites are unwanted, as they can be bitter or poisonous. Manipulating plant specialised metabolism is therefore highly desirable to produce increased quantities of high-value compounds or to reduce levels of unwanted components in certain plant parts. Such metabolic engineering is nowadays possible in principle. However, a better understanding of the processes underlying the production and the transport of specialised metabolites is key for efficient engineering, which is often missing for chemically complex plant compounds. The aim of this project is to obtain such knowledge using limonoids and quassinoids as an example. Limonoids and quassinoids are highly attractive targets for engineering. These biogenetically related triterpenes are mainly produced in citrus plants (Rutaceae) and in Simaroubaceae, respectively. The most well-known representative of the Simaroubaceae is the cosmopolitan weed Ailanthus altissima, the Chinese tree of heaven. Limonoids are responsible for the bitter taste of citrus fruits, whereas quassinoids are excreted by the Chinese tree of heaven to eliminate competing plants due to their phytotoxic properties. On the other hand, both limonoids and quassinoids possess beneficial properties: Many limonoids are potent insecticides or antiretroviral agents; quassinoids could be used as herbicides or as anti-cancer drugs. The aim of this project is to analyse how plants produce and transport limonoids and quassinoids, to establish a basis for better use of beneficial as well as avoidance of negative properties. Three subprojects will be employed to fulfil this aim: 1) Elucidating the biochemical basis of limonoid production by identifying biosynthesis genes from citrus plants. 2) Understanding and exploiting limonoid pathway logistics. Transporters will be identified by gene silencing, tested biochemically using an oocyte expression system and studied further using fluorescent substrate analogues. 3) Profiling quassinoid pathway in Chinese tree of heaven. Metabolome and transcriptome data from different tissues will be obtained and analysed. This project will provide a better understanding how limonoids and quassinoids are produced and transported in plants, and how this machinery can potentially be affected by metabolic engineering. Additionally, it will help to expand the knowledge about plant biochemistry and plant specialised metabolism in general.

来自植物的特殊代谢物已经被人类使用了数千年，其中许多仍然是基本的药物。然而，有时候，特殊的代谢物是不需要的，因为它们可能是苦的或有毒的。因此，操纵植物的特殊代谢是非常必要的，以产生更多的高价值化合物或减少某些植物部分中不需要的成分的水平。这种代谢工程如今在原则上是可能的。然而，更好地了解特殊代谢物的产生和运输的过程是高效工程的关键，这在化学复杂的植物化合物中经常缺失。本项目的目的是以柠檬类和拟西番莲类为例来获得这些知识。柠檬类和拟西芹类是极具吸引力的工程靶点。这些生物相关的三萜主要分别产生于柑橘类植物（芸香科）和香茅科。象鼻草科最著名的代表是遍布世界的臭椿，中国的天树。柠檬素是柑橘类水果苦味的原因，而番石榴素是由中国天树排出的，以消除竞争植物，因为它们具有植物毒性。另一方面，柠檬素和拟西柚素都具有有益的特性：许多柠檬素是有效的杀虫剂或抗逆转录病毒药物；番石榴素可以用作除草剂或抗癌药物。这个项目的目的是分析植物如何产生和运输柠檬素和类桂素，为更好地利用有益的和避免有害的特性奠定基础。为了实现这一目标，将开展三个子项目：1)通过鉴定柑橘植物的生物合成基因来阐明类柠檬素生产的生化基础。2)了解和开发柠檬素通路物流。转运体将通过基因沉默鉴定，使用卵母细胞表达系统进行生化测试，并使用荧光底物类似物进一步研究。(3)中国天树类人猿路径分析。将获得和分析来自不同组织的代谢组和转录组数据。该项目将更好地了解植物中柠檬素和番石榴素是如何产生和运输的，以及代谢工程如何潜在地影响这一机制。此外，它将有助于扩大对植物生物化学和植物专门代谢的一般知识。