Regulation of source-sink development and leaf homeostasis in vascular plants that translocate monoterpenes as photo-assimilates in addition to sugars such as sucrose

除了蔗糖等糖之外，维管束植物还以光同化物形式转运单萜，对源库发育和叶片稳态的调节

• 批准号: 7188-2011
• 负责人: Grodzinski, Bernard
• 金额: $ 1.75万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=474209
• 关键词: Regulation; source; sink; development; leaf

Vascular plants are complex eukaryotes that are photoautotrophs. They are desirable bio-reactors because they offer a sustainable source of organic compounds essential to our survival and well being. Plants have evolved multiple survival mechanisms for dealing with environmental stress. Their spatial and temporal, phenotype plasticity is unique in biology as plants regulate energy flow, initially solar energy trapped by the photosynthetic canopy into stable and mobile forms of reduced C, N and S. A primary source of photoassimilates is the leaf canopy, but, during vegetative and reproductive cycles contrary to popular belief other organs also contribute photoassimilates. If we are to exploit plants as bio-reactors for traditional (e.g., food, starch, sugars, amino acids, vitamins, etc) and novel bio-products (e.g., fuel, pharmaceuticals) our understanding of assimilate fluxes from source organs/tissues to developing sinks must improve. For example, the forms of reduced-C that are translocated via vascular phloem vary depending on the environmental stress and status of canopy development. Source-sink interactions determine productivity yet metabolite fluxes remain one of poorest understood plant processes. Selecting genes that can be targeted by either classical breeding protocols or using molecular bio-technologies to improve productivity of herbaceous and woody crops requires quantification of transport fluxes. In the Biotron facilities at Guelph we have engineered new analytical tools that are required to quantify phenotype plasticity at the organism, organ and organelle levels. In this project we will test new breeding lines, novel ecotypes and transgenics each with different genetic abilities to synthesize and transport large amounts of newly reduced C as monoterpenes (glucose esters such iridoids) as well as the better recognized sugar disaccaride, sucrose. Of particular interest as a model botanical family is the "newly" reclassified botanic family, the Plantaginaceae. These will be compared to selected members of the Leguminosea and the Brassicaeae as we have an opportunity to also test how targeted genetic modification of leaf shape and sink respiratory activity has altered efflux of reduced-C from leaves.

维管植物是复杂的真核生物，是光合自养生物。它们是理想的生物反应器，因为它们提供了对我们的生存和福祉至关重要的有机化合物的可持续来源。植物进化出了多种应对环境压力的生存机制。它们的空间和时间、表型可塑性在生物学中是独特的，因为植物调节能量流，最初太阳能被光合作用冠层捕获，转化为稳定和移动形式的减少的碳、氮和硫。光同化物的主要来源是叶冠，但是，与普遍看法相反，在营养和生殖周期中，其他器官也贡献光同化物。如果我们要利用植物作为传统生物产品（例如食品、淀粉、糖、氨基酸、维生素等）和新型生物产品（例如燃料、药品）的生物反应器，我们必须提高对从源器官/组织到发展汇的同化通量的理解。例如，通过维管韧皮部转运的还原碳的形式根据环境压力和冠层发育状态而变化。 源库相互作用决定了生产力，但代谢通量仍然是人们最不了解的植物过程之一。选择可以通过经典育种方案或使用分子生物技术来提高草本和木本作物生产力的目标基因需要量化运输通量。在圭尔夫市的 Biotron 设施中，我们设计了新的分析工具，用于量化生物体、器官和细胞器水平的表型可塑性。 在这个项目中，我们将测试新的育种系、新的生态型和转基因品系，它们各自具有不同的遗传能力，以合成和运输大量新还原的碳作为单萜（葡萄糖酯，如环烯醚萜）以及更被认可的糖二糖，蔗糖。作为模式植物科，特别令人感兴趣的是“新”重新分类的植物科——车前草科。这些将与豆科和十字花科的选定成员进行比较，因为我们还有机会测试叶形状和库呼吸活动的定向基因改造如何改变叶中还原碳的流出。