Control of Hypocotyl Elongation by Blue Light in Arabidopsis Seedlings

详细描述植物用于感知和响应其光环境的机制对于完整理解植物发育是必要的，这对于那些关注植物在农业和生物技术中的实际应用的人来说是重要的。 该奖项资助的活动将提供有关光谱的蓝色区域如何对拟南芥幼苗生长和发育产生深远影响的分子水平细节。 待使用的突变体在被认为编码光受体的基因中具有损伤，例如隐花色素（cryptochromes）（NPH1和NPH2）和光激酶（NPH1）。 通过高分辨率测量突变体幼苗对蓝光的生长反应，并将其与野生型进行比较，将详细了解光感受机制如何运作。 还将创造和研究在一个以上的感光细胞中含有突变的植物。 这种对蓝光的生长反应的比较动力学分析将表明特定的感光体何时开始发挥其作用。 这些关于时间的信息将使得能够非常集中地基于基因组学来搜索由各种遗传鉴定的蓝光受体发出的生物化学途径打开或关闭的基因，以引起生长反应。 该项目的这一方面将采用代表拟南芥基因组的芯片上的DNA微阵列。 一旦这些蓝光调控基因被鉴定出来，将开始对其特性和功能的研究，以便在分子水平上了解信号通路。 预计光信号通路的分子细节将成为支持未来植物技术的知识基础的重要组成部分。 该奖项支持的研究也将通过博士后，研究生和本科生的参与影响教育。

A detailed description of the mechanisms plants use to sense and respond to their light environment is necessary for a complete understanding of plant development, which is important to those concerned with the practical uses of plants in agriculture and biotechnology. The activities funded by this award will provide molecular-level details about how the blue region of the light spectrum exerts its profound effects on Arabidopsis seedling growth and development. The mutants to be employed have lesions in genes that are believed to encode light receptors, such as the cryptochromes (CRY1 and CRY2) and photokinase (NPH1). By measuring the growth responses to blue light of the mutant seedlings with high resolution, and comparing them to the wild type, details will be learned about how the photoreception mechanism operates. Plants containing mutations in more than one photoreceptor will also be created and studied. This comparative kinetic analysis of the growth responses to blue light will indicate when a particular photoreceptor begins to exert its effect. Such information on timing will enable a very focused genomics-based search for genes that are turned on or off by biochemical pathways emanating from the various genetically-identified blue light receptors to cause the growth responses. This aspect of the project will employ microarrays of DNA on chips that represent the Arabidopsis genome. Once such blue-light regulated genes are identified, studies of their properties and functions will be initiated so that the signaling pathway becomes known at the molecular level. It is expected that the molecular details of light-signaling pathways will be an important component of the knowledge base that will support plant technologies of the future. The research supported by this award will also impact education through the involvement of postdoctoral, graduate, and undergraduate students.