Integrated analysis of stem cell function in plant growth and development

干细胞在植物和动物的发育中都起着至关重要的作用，因为它们是一种自我维持的非特化细胞储存库，为组织和器官的形成提供前体细胞。干细胞有维持自身的能力，也能产生具有不同特征的子细胞（称为“分化”细胞）。因此，干细胞的维持对所有多细胞生物都是至关重要的，对医学和农业的再生生物学具有重要意义。考虑到干细胞的终身重要性，它们被安全地藏在所谓的干细胞壁龛中，以避免受到伤害，这些壁龛提供了一个促进自我更新和抑制细胞分化成不同细胞类型的微环境。植物干细胞生态位位于根和茎尖的分生组织中，在整个植物生命周期中对新器官和组织的产生至关重要，在某些物种中可以跨越数千年。在木本植物中，茎内的另一个专门的圆柱形分生组织形成层在次生增厚中起着特别重要的作用，从而产生木质物质，这也包含了干细胞。在这个建议中，我们试图使用微阵列分析来识别控制这些不同干细胞群体行为的基因。微阵列允许同时测量样品中所有基因的表达。我们将结合先进的细胞分选技术和技术，通过转基因调节来增加干细胞的数量，这将使我们能够识别控制不同干细胞增殖的共同和独特机制，以及它们是否以及何时分化为各自组织中的不同细胞类型。在植物中，这些指定和维持干细胞和相关基因的信号知之甚少。我们还试图了解干细胞如何对来自环境的线索作出反应。我们建议建立一个欧洲网络，由世界领先的研究小组组成，包括：(1)根干细胞（Ben Scheres，荷兰乌得勒支），(2)茎干细胞（Thomas Laux，德国弗莱堡），(3)形成层干细胞（Yka Helariutta，芬兰赫尔辛基），以及细胞分裂控制专家Jim Murray（英国剑桥）和生长植物组织图像分析专家Aurelio Camphilo（葡萄牙波尔图）。

Stem cells are of central importance in the development of both plants and animals, since they are a self-maintaining reservoir of unspecialised cells that provide the precursor cells for tissue and organ formation. Stem cells have the ability to maintain temselves and also to produce daughter cells with different characteristics (called 'differentiated' cells). The maintenance of stem cells is therefore crucial for all multicellular organisms and is of outstanding significance for regenerative biology in medicine and agriculture. Given the life-long importance of stem cells, they are tucked safely from harm's way, in so-called stem cell niches that provide a microenvironment promoting self-renewal and inhibiting cell differentiation into different cell types. Plant stem cell niches are located in meristems at root and shoot tips, and are pivotal to the production of new organs and tissues throughout the plant life cycle that in some species can span several thousand years. In woody plants a further specialised cylindrical meristem within the stem, the cambium, is of particular importance in secondary thickening that results in production of woody material, and this also contains stem cells. In this proposal, we seek to use microarray analysis to identify the genes that control behaviour of these different populations of stem cells. Microarrays allow simultaneous measurement of the expression of all genes in a sample. We will combine this with advanced cell sorting technologies and techniques to increase the number of stem cells by transgenic regulation, and this will allow us to identify common and distinct mechanisms that control the proliferation of different stem cells and whether and when they differentiate to give rise to different cell types in their respective tissues. In plants, these signals that specify and maintain stem cells and the genes involved are poorly understood. We also seek to understand how stem cells respond to cues from the environment. We propose a European network composed of the world leading groups involved in understanding (1) root stem cells [Ben Scheres, Utrecht, Netherlands], (2) shoot stem cells (Thomas Laux, Freiburg, Germany], (3) the cambial stem cells (Yka Helariutta, Helsinki, Finland), together with the group of Jim Murray (Cambridge, UK) who are experts in the control of cell division, and Aurelio Camphilo (Porto, Portugal), experts in image analysis of growing plant tissue.