SIGNALING ARREST OF POLLEN ACTIVATION THROUGH AQUAPORINS

通过水通道蛋白发出阻止花粉激活的信号

• 批准号: 6180558
• 负责人: JUNE B NASRALLAH
• 金额: $ 22.65万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 2002-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6180558
• 关键词: Cruciferae; Xenopus oocyte; antisense nucleic acid; autoimmunity; biological signal transduction; genetically modified plants; immunoelectron microscopy; laboratory rabbit; phosphorylation; pollen; protein kinase; protein localization; protein structure function; water channel; yeast two hybrid system

The goal of the proposed research is to determine how higher plants signal the arrest of a critical developmental pathway in the reproductive cycle. The experimental system is that of receptor- mediated signalling in the self-incompatibility response of Brassica, a genetically controlled self recognition system that prevents self- fertilization by arresting the development of genetically related pollen grains. Our cloning and characterization in 1991 of the receptor serine/threonine kinase that mediates this self-recognition, soon after the description in 1990 of the first member of the TGF-beta class of receptors with serine/threonine specificity, represented an important advance in our understanding of self-incompatibility and of cell-cell communication in plants. Our recent identification of a gene with sequence similarity to aquaporins (water channels) as an effector of receptor-mediated signalling in this system provides the first molecular evidence relating to the mechanism by which the activation and development of pollen is arrested. We propose to characterize this water channel, its cellular and subcellular distribution in plant cells, define its biophysical and biochemical properties, and determine its role in the arrest of pollen. In addition, we plan to identify other components of signal transduction in this system and construct a biochemical pathway that links the signalling receptor to activation of its putative downstream target, the water channel. When considered in light of work on receptors and water channels in hormone-induced activation of osmotic water permeability in mammalian cells, this study should provide for an informative comparison of the mechanisms by which the regulation of transcellular water transfer is achieved in organisms as divergent as plants and mammals.

这项拟议的研究的目标是确定高等植物如何 标志着一个关键的发育途径的停止 生殖周期。实验系统为受体系统。 甘蓝型油菜自交不亲和反应中的信号传递， 一种基因控制的自我识别系统，可以防止自我 通过阻止遗传相关花粉的发育来受精 谷物。我们在1991年克隆并鉴定了受体 丝氨酸/苏氨酸激酶，介导这种自我识别，不久之后 1990年对转化生长因子-β类的第一个成员的描述 具有丝氨酸/苏氨酸特异性的受体，代表着一种重要的 我们对自交不亲和性和细胞间亲和性的理解进展 植物中的交流。我们最近发现了一种基因 与水通道蛋白(水通道)作为效应因子的序列相似性 受体介导的信号传递在这个系统中提供了第一个分子 与激活和激活的机制有关的证据 花粉的发育受阻。我们建议对这片水域进行描述 通道，它在植物细胞中的细胞和亚细胞分布， 定义其生物物理和生化特性，并确定其 在阻止花粉传播方面发挥了重要作用。此外，我们计划确定其他 该系统中的信号转导组件，并构建一个 将信号受体连接到激活的生化途径 它假定的下游目标是水道。当考虑到 激素诱导的受体和水通道的研究进展 激活哺乳动物细胞的渗透水通透性，本研究 应提供关于以下机制的信息性比较： 跨细胞水转移的调节是在生物体中实现的。 就像植物和哺乳动物一样不同。