RUI: Root architecture and phase change, how two seemingly different aspects of plant development tie together

非技术性段落：植物根系的功能是从土壤中获取水分和矿质养分（肥料），以及锚定植物和防止土壤侵蚀。植物的根系通常由一个主根和多个分支组成，分支模式对植物的生长性能有重要影响。这个项目的重点是发现决定沿着主根放置分支根的机制。PI最近发现，根分支的模式随着植物在其生命周期的不同阶段的发展而变化。随着根分枝形态的早期变化，茎部叶片的排列也发生了变化，这就提出了叶片和根的位置是如何控制和协调的问题。这项工作的结果将通过增加对指导植物生长的基本原理的理解，并可能有助于培育更高产量的植物，或增强对水或营养物质（如氮）的获取或利用，从而增强美国在科学研究方面的领导地位。该项目还将通过直接让本科生参与研究，为培养下一代科学技术人才做出贡献，这种做法已被证明在招收和留住理工科学生方面是有效的。该项目还将支持地区高中生的实验室研究经验，他们将由PI和本科生指导，进一步扩大项目的教育和科学影响。长期以来，人们已经认识到植物枝条有不同的发育阶段。相比之下，尽管分生组织大小和根厚度的变化是已知的，但根系发育的阶段依赖性变化的潜力却很少受到关注。来自PI实验室的新数据表明，侧根的位置随着根的成熟而变化，而指导生长素运输的蛋白质对这些阶段的影响不同。此外，影响侧根定位的几个基因的功能丧失也会影响植物从幼叶到成熟叶排列模式的转换时间。该项目将：(1)确定根系发育变化的时间，并验证已知控制茎部相变的基因也控制根系相变的假设。它还将(2)研究已鉴定基因之间的遗传和分子相互作用，并验证关于根和茎中器官间距调节如何协调的假设。这个项目将增加本科生积极参与科学的机会，通过PI的实验室，通过一个有学分的课程，该课程将被修改，使参与这项研究成为教育经历的核心，并通过到Oberlin以外的一个领先的植物发育生物学实验室旅行的机会。PI和本科生还将与当地公立高中合作，将为期数天的调查实验带到高中，并为来自代表性不足群体的积极高中生创造机会，让他们在PI的实验室工作。

Non-technical paragraph: Plant roots function in acquiring moisture and mineral nutrients (fertilizer) from the soil, as well as anchoring the plant and preventing soil erosion. The root system of a plant is typically composed of a main root with multiple branches and the branching pattern has substantive impacts on the plant's performance. This project focuses on discovering the mechanisms that determine where along the main root the branch roots will be placed. The PI recently discovered that the pattern of root branching varies as plants progress through different stages of their life cycle. Coincident with an early change in the pattern of root branching, the arrangement of leaves in the shoot also changes, raising many questions about how the positioning of leaves and roots is controlled and coordinated. The results of this work will enhance the United States' position as a leader in scientific research by adding to the understanding of fundamental principles that guide plant growth and may contribute to the ability to breed plants with higher yields or enhanced acquisition or use of water or nutrients such as nitrogen. The project also will contribute to training the next generation in science and technology by directly involving undergraduate students in the research, a practice that has been shown to be effective in recruiting and retaining students in science. The project will also support laboratory research experiences for area high school students, who will be mentored by the PI and undergraduates, further extending the project's educational and scientific impact.Technical Paragraph: Distinct phases of development have long been recognized in plant shoots. In contrast, the potential for phase-dependent changes in root development receives little attention, although changes in meristem size and root thickness are known to occur. New data from the PI's laboratory show that the positioning of lateral roots varies as the root matures, and that proteins that direct auxin transport affect these stages differently. In addition, loss-of-function of several genes that affect lateral root positioning also affect the time at which plants switch from a juvenile to a mature pattern of leaf arrangement. This project will: (1) establish the timing of developmental changes that take place in the root and test the hypothesis that genes known to control phase change in the shoot also control phase in the root. It will also (2) investigate genetic and molecular interactions between the identified genes and test hypotheses as to how regulation of organ spacing in the root and shoot are coordinated. This project will increase the opportunities for undergraduates to actively participate in science through the PI's laboratory, through a credit-bearing course that will be revised to make involvement in this research the centerpiece of the educational experience, and through opportunities for travel to a leading plant developmental biology laboratory outside of Oberlin. The PI and undergraduates will also partner with the local public high school, bringing multi-day investigative experiments to the high school and creating opportunities for motivated high school students from underrepresented groups to work in the PI's laboratory.