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: 2910418
• 负责人: JUNE B NASRALLAH
• 金额: $ 22万
• 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/2910418
• 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.

这项研究的目的是确定高等植物 标志着一个关键的发展途径的逮捕， 生殖周期 实验系统为受体- 介导的信号传导在芸苔属的自交不亲和反应中， 一种基因控制的自我识别系统， 通过阻止遗传上相关的花粉的发育而受精 晶粒 我们在1991年克隆和鉴定了 丝氨酸/苏氨酸激酶介导这种自我识别，不久后， 在1990年描述的第一个成员的TGF-β类， 受体与丝氨酸/苏氨酸特异性，代表了一个重要的 对自交不亲和性和细胞-细胞关系认识的进展 植物中的通讯 我们最近发现了一个基因， 与水通道蛋白（水通道）的序列相似性， 在这个系统中，受体介导的信号传导提供了第一个分子 与激活和 花粉发育受阻。我们建议将这些水 通道，其在植物细胞中的细胞和亚细胞分布， 定义其生物物理和生物化学特性，并确定其 在花粉捕获中的作用。 此外，我们计划确定其他 在这个系统中的信号转导组件，并构建一个 一种将信号受体与激活 它的下游目标水道 考虑时 光的受体和水通道的工作， 激活哺乳动物细胞的渗透水渗透性，这项研究 应提供一个翔实的机制比较， 在生物体中实现跨细胞水转移的调节 就像植物和哺乳动物一样不同。