Integrated Studies on Cellular and Physiological Roles of Higher Plant Plasmodesmata

高等植物胞间连丝细胞和生理作用的综合研究

• 批准号: 0315174
• 负责人: William Lucas
• 金额: $ 47.3万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-15 至 2007-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0315174&HistoricalAwards=false
• 关键词: Integrated; Studies; Cellular; Physiological; Roles

Although it has long been known that, in plants, plasmodesmata (PD) establish cytoplasmic continuity between neighboring cells, it has only recently been established that these intercellular organelles play a role in the cell-to-cell trafficking of information macromolecules (proteins and RNA). The first direct evidence for this role came from genetic, molecular and cellular studies of viral infection in plants. In these infected plants, viral encoded movement proteins (MPs) traffic cell to cell through PD and, in this process, they mediate the spread of infectious RNA/DNA. In view of this finding, the hypothesis was advanced that plants similarly utilize this PD macromolecular trafficking pathway to exert positional-dependent control over developmental and physiological processes. The corollary to this hypothesis was advanced that plants function as unique supracellular, rather than multicellular, organisms. Support for this supracellular model has been accumulating; in this regard, a seminal discovery was that a number of plant transcription factors have now been shown to function in a non-cell-autonomous manner, via movement through PD. The picture that is emerging is that this ability of PD to transport macromolecules extended the properties evolved by the eukaryotic nuclear pore complex to the junctions between neighboring cells, and thereby allowed plants to develop this novel regulatory pathway.In the present work, experiments are aimed at characterizing the molecular constituents of PD and the non-cell-autonomous protein (NCAP) translocation pathway. For these studies a range of experimental techniques will be employed that combine genetic, molecular, cellular, physiological and developmental approaches. The major goal over this funding period will be to identify potential regulators of NCAP trafficking/PD function using a mutant screening approach in Arabidopsis. These studies should provide much needed information on the molecular components that function in the establishment and regulation of the non-cell-autonomous translocation pathway of plants. The importance of this information to the areas of integrative plant biology and development will likely be through the development of a greater understanding of the events that underlie whole plant signaling. These long-distance signals, delivered via the plant vascular system, are presently thought to function in the integration of the plant's response to environmental and biotic stresses.The requested funds will permit the training of junior scientists in this area of integrative plant biology. The importance of these scientists to our society will be through the application of knowledge towards the development of novel controls over plant processes, including the allocation of resources to targeted organs. Such applications could well have major ramifications in terms of agriculture and animal/human nutrition/health.

虽然人们早就知道，在植物中，胞间连丝（PD）建立相邻细胞之间的细胞质连续性，它只是最近才被确定，这些细胞间的细胞器在细胞间的信息大分子（蛋白质和RNA）的运输中发挥作用。这种作用的第一个直接证据来自植物病毒感染的遗传、分子和细胞研究。在这些受感染的植物中，病毒编码的运动蛋白（MP）通过PD在细胞间运输，在这个过程中，它们介导感染性RNA/DNA的传播。鉴于这一发现，提出了植物类似地利用这种PD大分子运输途径对发育和生理过程施加位置依赖性控制的假设。这一假说的推论是，植物作为独特的超细胞生物而不是多细胞生物发挥作用。对这种超细胞模型的支持一直在积累;在这方面，一个开创性的发现是，许多植物转录因子现在已被证明通过PD运动以非细胞自主的方式发挥作用。这是新兴的图片是，这种能力的PD运输大分子扩展的真核细胞核孔复合物的属性进化到相邻cells之间的连接，从而使植物开发这种新的监管pathways.In目前的工作中，实验的目的是在表征PD和非细胞自主蛋白（NCAP）易位途径的分子组成。对于这些研究，将采用一系列结合遗传、分子、细胞、生理和发育方法的联合收割机实验技术。在此资助期间的主要目标将是确定潜在的监管机构的NCAP贩运/PD功能使用突变体筛选方法在拟南芥。这些研究将为植物非细胞自主转运途径的建立和调控提供急需的分子组成信息。这一信息的重要性，综合植物生物学和发展领域将可能是通过一个更好地了解整个植物信号的基础事件的发展。这些通过植物维管系统传递的远距离信号，目前被认为在植物对环境和生物胁迫的反应的整合中起作用。所申请的资金将允许在综合植物生物学这一领域培训初级科学家。这些科学家对我们社会的重要性将是通过知识的应用来开发对植物过程的新控制，包括将资源分配给目标器官。这种应用很可能在农业和动物/人类营养/健康方面产生重大影响。