Molecular Genetics of Arabidopsis thaliana

拟南芥分子遗传学

• 批准号: 9603821
• 负责人: Elliot Meyerowitz
• 金额: $ 164.88万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9603821&HistoricalAwards=false
• 关键词: Molecular; Genetics; Arabidopsis; thaliana

9603821 Meyerowitz Technical This research is directed toward revealing the genetic and molecular mechanisms by which Arabidopsis flowers develop. The experiments are divided into two areas. The first area is to understand the regulation and function of the floral organ identity genes APETALA3 and PISTILLATA. The genes code for MADS-box DNA-binding proteins, and the proteins bind DNA as a heterodimer. The research is: to find the genes that specify the initial expression pattern of the two genes, which will be done by mutagenesis of transgenic lines that will give novel phenotypes if either MADS-box gene is ectopically activated; and to find the downstream genes activated or repressed by the AP3/PI heterodimer by use of differential display-RT-PCR methods. The second area is to derive a general model for the control of pattern of cell division in shoot and floral meristems. This will be done by the molecular cloning of the CLAVATA1, CLAVATA3 and WIGGUM genes. Non-technical An unanswered question in the genetic analysis of development is that of pattern formation: How does a collection of equivalent cells such as a plant flower primordium or a vertebrate limb bud become spatially organized, so that it develops into a highly patterned collection of different cell types? At least two processes are involved: patterned cellular differentiation, to give the final pattern of cell types, and patterned cell division, to give the appropriate size and shape to the mature structure. Flowers provide a particularly good example of these aspects of pattern formation; flowers usually have a stereotyped pattern of organ types: sepals, petals, stamens, and central carpels. Many flowers also have defined numbers of each of these organ types. The flower of Arabidopsis thaliana plants, for example, has four sepals spaced evenly around the floral periphery, four petals interior to and alternate with the sepals, six stamens, and a compound ovary of two carpels. The experiments described here will reveal some of the cellular mechanisms by which cells are directed to divide in appropriate patterns in developing flowers, and by which they are instructed to differentiate into appropriate cell types for their positions. If they succeed, the research will result in new genetic and molecular models for the spatial control of organ identity, and for the spatial patterning of cell divisions in plant pattern formation. These models will, in turn, reveal the genetic principles of plant development, and will, in the future, enable experimental control of plant development.

9603821 Meyerowitz技术本研究旨在揭示拟南芥花发育的遗传和分子机制。 实验分为两个方面。 第一个领域是了解花器官身份基因APETALA 3和PISTILLATA的调控和功能。 这些基因编码MADS盒DNA结合蛋白，这些蛋白以异源二聚体的形式结合DNA。 该研究是：通过对转基因株系的诱变，发现指定这两个基因的初始表达模式的基因，如果MADS-box基因被异位激活，则转基因株系将产生新的表型;并通过使用差异显示-RT-PCR方法发现被AP 3/PI异源二聚体激活或抑制的下游基因。 第二个领域是获得一个通用的模式控制的细胞分裂在地上部和花分生组织。 这将通过CLAVATA 1、CLAVATA 3和WIGGUM基因的分子克隆来完成。 在发育的遗传学分析中，一个尚未回答的问题是模式的形成：一个等同细胞的集合，如植物花原基或脊椎动物的肢芽，是如何在空间上组织起来的，从而发展成为一个高度模式化的不同细胞类型的集合？ 至少涉及两个过程：模式化的细胞分化，以给出细胞类型的最终模式，以及模式化的细胞分裂，以给出成熟结构的适当大小和形状。 花提供了一个特别好的例子，这些方面的模式形成;花通常有一个固定的模式的器官类型：萼片，花瓣，雄蕊和中央心皮。 许多花也有这些器官类型的定义数量。 例如，拟南芥植物的花有四个萼片均匀地分布在花的外围，四个花瓣在萼片内部并与萼片交替，六个雄蕊和两个心皮的复合子房。 这里描述的实验将揭示一些细胞机制，通过这些机制，细胞被引导在发育的花中以适当的模式分裂，并被指示分化成适合其位置的细胞类型。 如果他们成功了，这项研究将为器官身份的空间控制以及植物图案形成中细胞分裂的空间模式提供新的遗传和分子模型。 这些模型反过来将揭示植物发育的遗传原理，并且在未来， 使实验控制植物的发展。