Control of Organ Initiation and Size by the AINTEGUMENTA Gene

AINTEGUMENTA 基因对器官起始和大小的控制

• 批准号: 9817992
• 负责人: Robert Fischer
• 金额: $ 48.8万
• 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: 1999
• 资助国家: 美国
• 起止时间: 1999-02-01 至 2004-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9817992&HistoricalAwards=false
• 关键词: Control; Organ; Initiation; Size; AINTEGUMENTA

To understand mechanisms that regulate cell proliferation associated with organ initiation and the determination of organ size, the function of the AINTEGUMENTA (ANT) transcription factor is being studied. ANT is an important regulator of cell proliferation that is responsible for organ primordia initiation and the determination of mature organ size and shape. 1) ANT is transcribed in meristematic cells that initiate all aerial lateral organ primordia, in marginal meristem cells that contribute to organ width and in meristematic procambium cells that generate the vascular system. 2) The loss-of-function ant mutant phenotype (i.e., no ovule integuments, reduction in floral organ size and number, narrow leaves) is associated with a decrease in cell proliferation. 3) In transgenic plants where ANT is transcribed from the strong 35S promoter, the gain-of-function phenotype (i.e., enlarged leaves, floral organs and ovules) is associated with increased cell proliferation. Thus, ANT provides a unique entry point into the signal transduction pathway(s) that link the control of cell proliferation with organ initiation and the determination of organ size and shape.To understand how cell proliferation is regulated during organogenesis, the PI will accomplish the following goals: 1) Determine the relationship between patterns of ANT transcription and cell proliferation during organogenesis. 2) Identify genes and sequences that control ANT transcription in meristematic cells. 3) Identify targets of the ANT transcription factor and determine their relationship to the control of cell proliferation and organogenesis. 4) Elucidate the role of an ANT interacting protein on the control of cell proliferation and organogenesis. 5) Obtain additional regulators of organogenesis by identifying mutationsthat suppress or enhance the phenotype of a weak mutant allele, ant-3. Results from these experiments will provide insight into fundamental mechanisms that control organ initiation and the determination of organ size and shape. They will help to elucidate the signal transduction pathways that control cell proliferation during organogenesis. This information will generate novel methods to modify organ size in crop plants, and thereby increase their productivity and value.

为了了解与器官起始和器官大小确定相关的细胞增殖调节机制，正在研究 AINTEGUMENTA (ANT) 转录因子的功能。 ANT 是细胞增殖的重要调节因子，负责器官原基的启动以及成熟器官大小和形状的决定。 1) ANT在启动所有气生侧向器官原基的分生组织细胞、有助于器官宽度的边缘分生组织细胞和产生维管系统的分生组织原形成层细胞中转录。 2）功能丧失的蚂蚁突变体表型（即没有胚珠珠被、花器官大小和数量减少、叶子狭窄）与细胞增殖的减少有关。 3) 在 ANT 从强 35S 启动子转录的转基因植物中，功能获得表型（即增大的叶子、花器官和胚珠）与细胞增殖的增加相关。 因此，ANT 为信号转导途径提供了一个独特的切入点，将细胞增殖的控制与器官起始以及器官大小和形状的确定联系起来。为了了解器官发生过程中细胞增殖的调节方式，PI 将实现以下目标：1) 确定器官发生过程中 ANT 转录模式与细胞增殖之间的关系。 2) 鉴定分生细胞中控制 ANT 转录的基因和序列。 3) 识别ANT转录因子的靶标并确定它们与细胞增殖和器官发生控制的关系。 4) 阐明ANT相互作用蛋白在细胞增殖和器官发生控制中的作用。 5) 通过鉴定抑制或增强弱突变等位基因ant-3表型的突变，获得器官发生的额外调节因子。这些实验的结果将提供对控制器官起始和确定器官大小和形状的基本机制的深入了解。 它们将有助于阐明器官发生过程中控制细胞增殖的信号转导途径。 这些信息将产生改变作物器官大小的新方法，从而提高其生产力和价值。