The acquisition of cellular asymmetry (polarity) is essential for generating cell diversity during eukaryotic development. Intrinsic or extrinsic cues orient cell polarity, but relatively little is known about how cells translate polarizing cues to establish and maintain a polarized state. The overall goal of this project is to advance our understanding of how plant cells become polarized in response to extrinsic cues. Previous work discovered a receptor-like protein, PAN1, which is implicated in perception of an extrinsic cue that polarizes cells during the development of stomata (epidermal pores) in maize leaves. Current project will build on these earlier findings using genetic, molecular and biochemical approaches to advance the understanding of mechanisms by which PAN1 promotes cell polarity marked by reorganization of the actin cytoskeleton and re-positioning of the nucleus. Specifically, the project will elucidate the connections between PAN1 and known regulators of actin polymerization, to identify a protein shown to be phosphorylated in a PAN1-dependent manner as well as a second gene, PAN2, which is required for the same processes as PAN1, and to elucidate the roles of the phosphoprotein and PAN2 in cell polarization. This work will advance the understanding of fundamental aspects of eukaryotic development that are misregulated in human diseases, and will also have a positive impact on science education. A postdoc, a graduate student, and an undergraduate will receive interdisplinary training through participation in this project. Project participants will develop and lead hands-on learning activities related to this project in a public San Diego Middle School. Thus, this project will contribute to future science and technology capabilities in the United States.
