Analysis of Meristem Function and Floral Patterning in the Arabidopsis ULTRAPETALA Mutant

拟南芥ULTRAPETALA突变体分生组织功能和花型分析

• 批准号: 0110667
• 负责人: Jennifer Fletcher
• 金额: $ 28.93万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0110667&HistoricalAwards=false
• 关键词: Analysis; Meristem; Function; Floral; Patterning

0110667FletcherThe control of stem cell activity is critical for the proper development of all higher organisms, as stem cells are the precursors of the organs and tissues that comprise the body. Plants make excellent model systems in which to study and manipulate stem cells, because they maintain pools of such cells throughout their life cycle at growing tips called apical meristems. The shoot apical meristem continuously maintains a stem cell reservoir while simultaneously generating organs such as leaves, stems and flowers. How the meristem keeps a constant balance between stem cell production and organogenesis is poorly understood, but studies by Dr. Fletcher and others using the model plant Arabidopsis thaliana are uncovering genes that regulate this balance and thereby affect shoot apical meristem activity. The goal of this project is to understand how the Arabidopsis ULTRAPETALA (ULT) locus controls the activity of shoot and floral meristems. We have isolated ult mutant plants that generate extra flowers and floral organs from enlarged meristems, and also have altered organ identity in the center of the flower. ULT is therefore a candidate regulator of both shoot apical meristem function and floral patterning. Our first objective is to identify the defect(s) underlying the ult shoot and floral meristem phenotypes by analyzing the distribution of region-specific molecular markers. We will also decipher the genetic relationship between ULT and other known regulators of shoot and flower development, which act in a number of different pathways. Our third goal is to map and clone the ULT gene, and determine its mRNA expression pattern during development as a prelude to functional analysis of the gene product. These experiments will identify specific mechanisms through which ULT regulates meristem size and floral patterning, and place ULT in context with other Arabidopsis genes known to affect these processes. Analysis of ULT provides a unique opportunity to investigate the mechanisms that balance life-long stem cell production and organogenesis, and also to determine how a single molecule functions both in growth control and pattern formation to coordinate these two crucial processes during development.

0110667弗莱彻干细胞活性的控制对于所有高等生物的正常发育至关重要，因为干细胞是组成身体的器官和组织的前体。 植物是研究和操纵干细胞的极好模型系统，因为它们在整个生命周期中在称为顶端分生组织的生长尖端维持着这样的细胞库。 茎尖分生组织持续维持干细胞库，同时产生器官，如叶，茎和花。分生组织如何在干细胞产生和器官发生之间保持恒定的平衡还知之甚少，但弗莱彻博士和其他人使用模式植物拟南芥的研究正在揭示调节这种平衡的基因，从而影响茎顶端分生组织的活动。本项目的目标是了解拟南芥ULTRAPETALA（ULTRAPETALA）基因座如何控制茎和花分生组织的活动。我们已经分离出ult突变体植物，它们从扩大的分生组织中产生额外的花和花器官，并且在花的中心也具有改变的器官特性。因此，茎尖分生组织的功能和花图案的候选调节剂。 我们的第一个目标是通过分析区域特异性分子标记的分布来确定最终茎和花分生组织表型的缺陷。 我们还将破译之间的遗传关系，以及其他已知的调节芽和花的发展，这在许多不同的途径。 我们的第三个目标是映射和克隆的p53基因，并确定其mRNA的表达模式在发展过程中的基因产物的功能分析的前奏。 这些实验将确定特定的机制，通过它调节分生组织的大小和花的图案，并放置在上下文与其他拟南芥基因已知影响这些过程。 对胚胎干细胞的分析提供了一个独特的机会来研究平衡终身干细胞生产和器官发生的机制，并确定单个分子如何在生长控制和模式形成中发挥作用，以协调发育过程中的这两个关键过程。