Understanding the mechanisms of developmental regulation by Arabidopsis Armadillo-related proteins.

所有多细胞生物，无论是动物、植物、真菌还是原生动物，都是由具有不同形式和功能的细胞群组成的。我感兴趣的是，在多细胞发育过程中，生物体内的细胞如何变得彼此不同，并获得专门的功能。生物体中的每个细胞在其细胞核中含有相同的总遗传物质。然而，遗传物质的调节方式（单个基因的开启和关闭）因细胞类型而异。细胞在生物体内获得特定的命运，如肌肉细胞或叶细胞，通过响应来自环境的信号。这些信号告诉他们打开和关闭哪些基因，从而产生哪些蛋白质。成为多细胞的过程有很大程度的分子保守性。相关的基因和蛋白质通常在完全不相关的生物体中执行相同的功能。我特别感兴趣的是Armadillo蛋白质家族。这些蛋白质在动物发育过程中指定细胞的命运，也在非动物中，社会阿米巴Dictyosteoba。这表明Armadillo蛋白的功能在多细胞生物进化过程中很早就出现了。我已经证明了与犰狳相关的蛋白质存在于植物王国中。使用拟南芥，鼠耳水芹，作为一个模型，我已经表明，拟南芥Armadillo蛋白影响根的发展。植物的根系统由从发芽的种子中长出的主根和在植物一生中从主根分支的侧根组成。当主根内的细胞分裂产生新的侧根时，拟南芥犰狳蛋白促进根分枝。植物根系的形状对植物生长至关重要。根允许植物从土壤中吸收水分和养分，允许我们在地面上看到的芽生长。虽然植物Armadillo蛋白调节的实际发育过程与动物不同（动物没有根!），很可能在小范围内，植物Armadillo蛋白功能的分子机制在动物和变形虫中是保守的。Arabidopsis Armadillo蛋白存在于细胞核中，就像它们的动物亲戚一样。我计划了解拟南芥Armadillo蛋白如何通过详细研究它们在细胞内的位置，它们与其他蛋白质相互作用，以及这些相互作用的蛋白质如何修改Arabidillo功能来执行它们的细胞作用。通过揭示拟南芥Armadillo蛋白在植物中的功能机制，我将提供一个新的理解如何发生根的发展。根系构型必须是动态的，植物才能对环境条件的变化做出反应，如水和养分的可用性。因此，拟南芥Armadillo蛋白质影响与农业相关的过程，而不仅仅是实验室实验。了解这些蛋白质的功能将有助于使植物更好地适应其生长环境的变化。

All multicellular organisms, whether animals, plants, fungi or protozoa, are composed of groups of cells with diverse forms and functions. I am interested in how cells within an organism become different from each other and acquire specialised functions during the process of multicellular development. Each cell in an organism contains the same total genetic material in its nucleus. However, the way the genetic material is regulated (which individual genes are turned on and off) differs between cell types. Cells acquire particular fates within an organism, such as muscle cells or leaf cells, by responding to signals from their environment. These signals tell them which genes to turn on and off, and therefore which proteins to make. The process of being multicellular has a great degree of molecular conservation. Related genes and proteins often perform the same function in quite unrelated organisms. My particular interest is in the Armadillo protein family. These proteins specify cell fates during animal development, and also in a non-animal, the social amoeba Dictyostelium. This suggests that the function of Armadillo proteins arose very early during the evolution of multicellular organisms. I have shown that proteins related to Armadillo are present in the plant kingdom. Using Arabidopsis, mouse-ear cress, as a model, I have shown that Arabidopsis Armadillo proteins affect root development. A plant's root system is made up of a primary root that emerges from the germinating seed, and of lateral roots that branch from the primary root throughout the plant's life. Arabidopsis Armadillo proteins promote root branching, which occurs when cells within the main root divide to produce a new, lateral, root. The shape of a plant's root system is critical for plant growth. Roots allow the plant to take up water and nutrients from the soil, allowing the shoot that we see above ground to grow. Although the actual developmental process being regulated by plant Armadillo proteins is not the same as in animals (animals do not have roots!), it is quite possible that at the small scale, the molecular mechanisms by which plant Armadillo proteins function are conserved with animals and amoebae. Arabidopsis Armadillo proteins are found in the nucleus of cells, like their animal relatives. I plan to understand how Arabidopsis Armadillo proteins perform their cellular role by looking in detail at where they localise to within cells, what other proteins they interact with, and how these interacting proteins modify Arabidillo function. By uncovering the mechanisms of Arabidopsis Armadillo protein function in plants I will provide a new understanding of how root development occurs. Root architecture must be dynamic, for plants to respond to changes in environmental conditions, such as water and nutrient availability. Thus, Arabidopsis Armadillo proteins affect a process of relevance to agriculture, not just to a laboratory experiment. Understanding these proteins' functions will suggest ways of making plants better-adapted to coping with changes in the environment in which they grow.