CAREER: Linking Lateral Cell Polarity with Tissue Patterning in Plant Development

细胞分裂和特化是多细胞生物体生长和发育过程中必不可少的过程。与动物系统相比，关于植物如何调节细胞分裂和特化的机械论见解有限，这与细胞极性有关。细胞的极性被定义为在发育或生理的任何方面沿一个轴的不对称性，而蛋白质的不对称定位是极化细胞的常见属性。在此之前，人们发现了一组受体激酶，它们在不同的细胞类型中表现出极性的定位，并在发育过程中发挥作用。这些蛋白质为研究植物细胞的极性提供了一套新的概念和分子工具。该学院早期职业发展(CALEAR)项目的目标是研究细胞极性和发育之间的联系，并整合旨在提高本科生对生物学的参与度和留存能力的积极研究模块。这些单元将在实验室课程中进行，在该课程中，学生将参与真实的研究并生成将直接整合到研究项目中的材料。这门高度互动的课程将建立一个包括同行、研究生和教职员工在内的科学社区。建立共同体意识和为更大的事物做出贡献是培养当今学生的科学热情和专业知识的基本要素。除了那些参与运输的蛋白质外，很少有具有极地定位的植物蛋白质被表征。一组跨膜受体激酶，POLARLY定位激酶(PLKs)，定位于不同类型根细胞的侧向(内/外)质膜区，在器官构型中发挥作用。推测PLK通过其定向信号转导功能直接影响根发育中的细胞分裂和分化。为了确定侧向细胞极性和组织构型之间的机制联系，这个职业项目的目标是：1)表征PLK的发育作用，2)阐明PLK极性定位的细胞学机制，3)剖析PLK功能和定位结构域以确定极性基序。这个项目准备从不同于定向运输的角度来研究植物细胞极性是如何建立和维持的，并支持长期存在的假设，即定向信号和位置信息是植物发育的关键驱动因素。该项目的短期更广泛影响将是获取和传播基本信息以及招募和培训STEM学生。学生将接受关于遗传学和分子方法以及尖端显微镜技术的培训；项目的规划和执行；以及有效的科学交流，以确立他们作为学者和导师的地位。从长远来看，所获得的知识可以作为有选择地利用现有的或产生改良的根性状的基础，从而使根功能最大化并支持植物生产力。此外，这项研究可能揭示动物系统中细胞极性机制的相似之处，提供一个框架来确定多细胞真核生物的极性和发展的共同逻辑。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Cell division and specialization are essential processes in the growth and development of multicellular organisms. In comparison to animal systems, there is limited mechanistic insight into how plants modulate cell division and specialization with respect to cell polarity. Cell polarity is defined as asymmetry in any aspect of development or physiology along a single axis and asymmetric protein localization is a frequent attribute of polarized cells. Previously a set of receptor kinases was identified that display polar localization in various cell types and have roles in development. These proteins provide a novel set of conceptual and molecular tools to investigate cell polarity in plants. The goals of this Faculty Early Career Development (CAREER) project is to study the links between cell polarity and development and to integrate active research modules designed to improve engagement and retention of undergraduate students in biology. These modules will be conducted in a laboratory course in which students will engage in authentic research and generate materials that will be directly integrated into the research project. This highly interactive course will establish a scientific community that includes peers, graduate students, and faculty. Building a sense of community and contribution to something larger are essential elements in the cultivation of scientific passion and expertise in today's students.Beyond those proteins involved in transport, very few plant proteins with polar localization have been characterized. A group of transmembrane receptor kinases, POLARLY LOCALIZED KINASEs (PLKs), are localized to the lateral (inner/outer) plasma membrane domains of various root cell types and have roles in organ patterning. It is hypothesized that PLKs directly influence cell division and differentiation in root development through their function in directional signaling. To identify mechanistic links between lateral cell polarity and tissue patterning this CAREER project aims to: 1) characterize the developmental roles of PLKs, 2) elucidate the cellular mechanics of PLK polar localization, and 3) dissect PLK functional and localization domains to identify polarity motifs. This project is poised to address how plant cell polarity is established and maintained from a perspective distinct from directional transport, and which, supports the long standing hypothesis that directional signaling and positional information are key drivers of plant development. The short-term broader impacts of this project will be the acquisition and dissemination of basic information and the recruitment and training of STEM students. Students will receive training in genetic and molecular approaches and cutting-edge microscopy techniques; planning and execution of projects; and, effective scientific communication to establish themselves as scholars and mentors. In the long term, the acquired knowledge can serve as a foundation to selectively exploit existing or generate improved root traits that maximize root function and support plant productivity. In addition, this study may reveal parallels to cell polarity mechanisms in animal systems, providing a framework to identify a common logic to polarity and development across multicellular eukaryotes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.