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.
