Interactions of growth and pattern formation mechanisms in plant development

随着生物体的生长，基因表达模式的出现有助于塑造各种器官和结构。基因表达和形态之间的相互作用是复杂的，而且鲜为人知。部分问题在于缺乏定量评估组织生长和构图的方法。植物叶片为研究生长和构图之间的关系提供了一个特别有趣的系统，因为叶脉形成和叶片生长是紧密耦合的，而植物激素生长素在这两个过程中都发挥着重要作用。这一建议旨在以定量的方式研究生长素运输、生长和脉纹形成之间的联系。首先，我将使用我开发的静脉模式分析软件，研究随着叶子的生长而导致静脉形成的间隔机制。其次，我将研究在三个模式物种中，物种之间以及叶片和花瓣之间的模式形成机制的共性。第三，我将开发一种在叶片发育的叶脉模式阶段监测叶片生长的方法，这将使定量测试叶脉模式与生长之间的相互作用成为可能。第四，利用植物细胞培养研究生长素流向对细胞极性和生长的影响。这项工作将为脉纹形成和生长过程带来新的见解，并将为利用模拟建模探索纹路形成机制提供有力的基础。我们相信，计算和实验工作的结合将是理解植物形态发生机制的关键手段。潜在的应用包括园艺和作物改良，因为植物维管系统与植物形态和生物量密切相关。我们还相信，这项研究将对整个发育生物学领域产生重大影响，因为它是研究生长和模式形成之间关系的最早尝试之一。植物生物学以外的应用领域包括癌症生物学(肿瘤形态发生的控制)。

As an organism grows, patterns of gene expression emerge which are instrumental in shaping a variety of organs and structures. Interactions between gene expression and morphology are complex and little understood. Part of the problem lies in a lack of methods for assessing tissue growth and patterning quantitatively.  Leaves provide a particularly interesting system for investigating the relationships between growth and patterning, as vein pattern formation and leaf growth are closely coupled, and the plant hormone auxin plays a major role in both processes.  This proposal aims at investigating the link between auxin transport, growth and vein pattern formation in a quantitative way. First, I will investigate spacing mechanisms leading to vein formation as leaves grow, using vein pattern analysis software I developed. Second, I will investigate the generality of patterning mechanisms between species, and between leaves and petals, in three model species. Third, I will develop a method for monitoring leaf growth during the vein patterning phase of leaf development, which will make it possible to test the interactions between vein patterning and growth quantitatively. Fourth, I will investigate the effect of auxin flow direction on cell polarity and growth using plant cell cultures.  This work will bring new insights in vein pattern formation and growth processes, and will provide a strong basis for exploring pattern formation mechanisms using simulation modeling. We believe that the combined use of computational and experimental work will be a key instrument for understanding mechanisms of plant morphogenesis. Potential applications include horticulture and crop amelioration, as plant vasculature is closely related to plant morphology and biomass. We also believe this research will have a major impact in the field of developmental biology as a whole, as it represents one of the first attempts to investigate the relations between growth and pattern formation. Domains of application outside plant biology include cancer biology (control of tumor morphogenesis).