Root Meristem Architecture: The Role of the Quiescent Center

根分生组织结构：静止中心的作用

• 批准号: 9404842
• 负责人: Lewis Feldman
• 金额: $ 24.17万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-01 至 1999-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9404842&HistoricalAwards=false
• 关键词: Root; Meristem; Architecture; Role; Quiescent

Root apices have been studied through the analysis of cell lineage based on histological sections. Theories of apical organization derived from such analyses led to the view that there existed "ultimate initials" at the focus of the cell lineage, just proximal to the root cap. As a result of continuous mitotic activity, it was believed, the ultimate initials produced derivative cells that formed the root. The discovery in 1956 that these cells rarely divided in a growing root initiated a reassessment of root development. Collectively, these inactive "ultimate initials" comprise a region called the quiescent center (QC). Since its discovery, plant biologists have tried to understand what the QC cells do, why they are quiescent, and how and when quiescence arises. The work outlined in this proposal addresses these questions. The objectives of this proposal are to use molecular, genetic, and physiological approaches to link the known biochemistry of the root to the biophysics which determines the cellular architecture of the root. Specific attention will be directed to measuring the levels, distributions and interactions between auxin, ascorbic acid and ascorbic acid oxidase with the objective of relating changes in these substances to properties of the quiescent center. Using various experimental approaches, levels of these substances will be manipulated and the status of the quiescent center and apical anatomy investigated. The significance of this effort lies in the advancement of a new hypothesis to account for and understand the establishment and developmental role of the quiescent center and ultimately patterning in roots.

通过基于组织学切片的细胞谱系分析，已经研究了根尖。 从这种分析中得出的顶端组织的理论导致这样的观点，即在细胞谱系的焦点上存在“最终的缩写”，只是靠近根上限。 人们认为，由于连续有丝分裂活性，最终的缩写产生了形成根部的衍生细胞。 1956年的发现，这些细胞很少在不断增长的根中分裂，从而重新评估了根发育。 总的来说，这些不活动的“最终缩写”包括一个名为Quiescent Center（QC）的区域。 自发现发现以来，植物生物学家试图了解QC细胞的作用，为什么它们是静止的以及如何以及何时出现的。 该提案中概述的工作解决了这些问题。 该建议的目标是使用分子，遗传和生理方法将根的生物化学与决定根的细胞结构的生物物理学联系起来。 特定的注意力将用于测量生长素，抗坏血酸和抗坏血酸氧化酶之间的水平，分布和相互作用，目的是将这些物质的变化与静态中心的性质联系起来。 使用各种实验方法，将操纵这些物质水平，并研究了静态中心和根尖解剖结构的状态。 这项努力的重要性在于提高了一个新的假设，以说明和理解静态中心的建立和发展作用，并最终在根中构图。