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.

维管植物是一种复杂的真核生物，是光自养生物。它们是令人向往的生物反应堆，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。植物已经进化出多种生存机制来应对环境胁迫。它们在空间和时间上的表型可塑性在生物学上是独一无二的，因为植物调节能量流动，最初被光合作用冠层捕获的太阳能转化为稳定和移动的还原的碳、氮和硫。光同化物的主要来源是叶冠，但在营养和生殖周期中，与普遍认为的相反，其他器官也贡献光同化物。如果我们要利用植物作为传统(如食物、淀粉、糖、氨基酸、维生素等)和新型生物产品(如燃料、药品)的生物反应器，我们必须提高对从来源器官/组织到发展中的汇的同化通量的理解。例如，通过维管束韧皮部运输的还原碳的形式因环境胁迫和冠层发育状况而异。源-库相互作用决定生产力，但代谢物通量仍然是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植物和木本植物生产力的基因，需要量化运输通量。在Guelph的Biotron设施中，我们设计了新的分析工具，这些工具需要在有机体、器官和细胞器水平上量化表型可塑性。在这个项目中，我们将测试新的育种品系、新的生态型和转基因材料，每个转基因材料都具有不同的遗传能力，以合成和运输大量新减少的C作为单萜类(葡萄糖酯，如环烯醚类化合物)以及更好地识别的二糖类，蔗糖。特别令人感兴趣的模式植物科是“新的”重新分类的植物科，车前科。这些将与豆科和十字花科中选定的成员进行比较，因为我们有机会也测试叶形和下沉呼吸活动的定向基因改造如何改变叶片中还原-C的外流。