Understanding the molecular mechanism of vein formation in Arabidopsis

了解拟南芥静脉形成的分子机制

• 批准号: 183891-2012
• 负责人: Schultz, Elizabeth
• 金额: $ 1.82万
• 依托单位: University of Lethbridge
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=593636
• 关键词: Understanding; molecular; mechanism; vein; formation

Our research works towards understanding the molecular mechanisms controlling vein formation. The vascular system is fundamental to plant structure and function, providing a skeleton and efficient transport routes for water, photosynthates, essential nutrients, pathogens and signaling compounds. In fact, because of improved water delivery to photosynthesizing cells, the density of veins is a key predictor of photosynthetic efficiency within diverse plants through evolutionary time. Thus, our findings may inform and allow plant modifications designed to improve photosynthetic capacity or withstand drought stress. The factors identified as being important to vein formation are primarily involved in transport of the plant hormone, auxin. Auxin is fundamental to a huge number of plant developmental processes, including embryo polarity, root organization, placement of branch roots and leaves and response to gravity and light. In all processes directional auxin transport through asymmetric placement of auxin efflux proteins on cell membranes is critical to auxin function. Vein pattern seems to be sufficiently complex that screens for vein pattern mutants reveal novel auxin transport components with either redundant roles or effects too subtle to be detected in classical screens for root or embryonic defects. Thus, beyond providing a better understanding of vascular formation, our work will reveal molecular mechanisms controlling auxin localization and activity throughout plant development. We have found two genes, FORKED1 and UNHINGED that are important for asymmetric placement of auxin efflux proteins in developing cells. We will define more precisely how the protein products of these genes work though establishing where they act in the cell, what proteins they form complexes with and how their expression, localization and partnerships are regulated. As well, we will identify new genes important to coordinating vein pattern with leaf shape and controlling the density of veins within the leaf.

我们的研究致力于了解控制静脉形成的分子机制。维管系统是植物结构和功能的基础，为水、光合产物、必需营养素、病原体和信号化合物提供骨架和有效的运输路线。事实上，由于向光合作用细胞的水分输送得到改善，静脉密度是不同植物在进化过程中光合作用效率的关键预测因素。因此，我们的研究结果可能会告知并允许对植物进行改造，以提高光合能力或抵御干旱胁迫。被认为对静脉形成重要的因素主要涉及植物激素生长素的运输。生长素是许多植物发育过程的基础，包括胚胎极性、根组织、枝根和叶子的位置以及对重力和光的反应。在所有过程中，通过生长素流出蛋白在细胞膜上的不对称放置进行定向生长素转运对于生长素功能至关重要。静脉模式似乎足够复杂，以至于对静脉模式突变体的筛选揭示了新的生长素运输成分，这些成分具有多余的作用或过于微妙的作用，无法在经典的根或胚胎缺陷筛选中检测到。因此，除了更好地理解维管形成之外，我们的工作还将揭示在整个植物发育过程中控制生长素定位和活性的分子机制。我们发现了两个基因：FORKED1 和 UNHINGED，它们对于发育细胞中生长素流出蛋白的不对称放置非常重要。我们将通过确定这些基因的蛋白质产物在细胞中的作用位置、它们与哪些蛋白质形成复合物以及它们的表达、定位和伙伴关系如何受到调节，来更精确地定义这些基因的蛋白质产物如何发挥作用。此外，我们还将鉴定对于协调叶脉图案与叶子形状以及控制叶内叶脉密度很重要的新基因。