Circadian Regulation of Auxin Signal Transduction

地球上的每一种生物都必须适应不断变化的环境。动物可以通过远离环境压力来应对环境压力；然而，对于植物来说，这不是一个选择，它们实际上是扎根在原地的。因此，植物已经发展出复杂的方式来调节它们的生理和发育，以响应它们特定的生长环境，并预测由于地球自转而每天发生的变化。人们在生物钟和植物激素生长素之间发现了一种意想不到的联系，生物钟以一种特定的时间方式调节植物生理的许多方面，而植物激素生长素控制植物生长和发育的许多空间方面。一个令人惊讶的发现是，生物钟至少控制着植物对生长素的一些反应：植物对生长素的反应在一天中的不同时间给予不同的生长素。在目前的项目中，生物钟和生长素反应之间的联系将使用遗传学、基因组学和先进的成像技术进行研究。这项研究将有助于确定1)生长素反应的各个方面，如定向生长是否也受到时钟的调节；2)植物器官对生长素反应的时钟调节是在哪些情况下发生的；3)生长素反应的时钟调节的分子基础。我们将深入了解生物钟和生长素信号这两条重要的调节途径如何相互作用。这一信息将对研究植物正常发育和植物对环境胁迫反应的科学家产生极大的兴趣，并可能在未来应用于优化作物物种在可变环境中的生长。此外，本提案中概述的工作将为高中、大学、研究生和研究生阶段的学生提供宝贵的实践培训。此外，研究成果将展示给高中学生、教师和本科生，以促进公众对科学的理解和支持。

Every organism on earth must cope with a constantly changing environment. Animals can deal with environmental stress by moving away from it; however, this is not an option for plants, which are literally rooted in place. Plants have therefore developed sophisticated ways to regulate their physiology and development both in response to their specific growth environment and in anticipation of changes that occur each day due to the earth's rotation on its axis. An unexpected connection has been found between the circadian clock, which regulates many aspects of plant physiology in a time-of-day specific manner, and the plant hormone auxin, which controls many spatial aspects of plant growth and development. A surprising finding is that the circadian clock controls at least some plant responses to the hormone auxin: plants respond differently to auxin when it is administered at different times of day. In the current project, the connection between the circadian clock and auxin responses will be investigated using genetic, genomic, and advanced imaging techniques. This research will help determine 1) whether aspects of auxin responses such as directional growth are also under clock regulation, 2) in which plant organs clock regulation of auxin responses occurs, and 3) the molecular basis of clock regulation of auxin responses. Fundamental insights into how two important regulatory pathways, the circadian clock and auxin signaling, interact with each other are expected. This information will be of great interest to scientists studying both normal plant development and plant responses to environmental stresses, with possible future applications in optimizing growth of crop plant species in variable environments. In addition, the work outlined in this proposal will provide valuable hands-on training for students at the high school, college, graduate, and post-graduate levels. Furthermore, research findings will be presented to high school students, teachers and undergraduates in an effort to promote the understanding and support of science by the general public.