This project explores how a specialized cellular structure termed the P-body is involved in gene regulation, elicited upon plant pathogen infection to provide a means for hosts to launch a prominent layer of defense response. Cellular signal transduction consists of a coordinated series of molecular events that is pivotal for regulation of gene expression, and thus is essential for all organisms to survive. Perception of pathogen attack elicits robust plant immune responses at the cellular level, including rapid and profound alterations in the expression of specific genes. However, the molecular mechanisms underlying the role of various RNA regulations in the immune response is currently unclear. This project addresses such critical gaps by deciphering the role of the P-body in messenger RNA regulation. This question will be addressed through an integrated systems approach in the model plant Arabidopsis thaliana. These activities will provide research training for two undergraduate students, three PhD students, and two postdoctoral researchers, as well as outreach activities such as an annual workshop. Besides advancing fundamental understanding of cellular dynamics, signal transduction and gene regulation, new high-throughput methods will be developed that have the potential to be applied in other topics of research.
The hypotheses to be tested are formulated based on recent preliminary results indicating that P-body assembly plays an important role in plant immunity. Genetic, molecular, and biochemical approaches in Arabidopsis will be employed, including a state-of-the-art method to identify RNA elements bound by a central P-body component, the TZF1 tandem CCCH zinc finger protein. The first set of experiments will test if P-body dynamics functions as a highly regulated process in orchestrating gene expression at the post-transcriptional level during plant biotic stress responses. By performing time-course kinetic analyses, it is expected to reveal the mechanisms by which P-body dynamics modulates mRNA fates in balancing host growth and stress adaptation. The second set of experiments aims to elucidate the mechanism by which TZF1 targets and regulates mRNA stability. Because the TZF gene family is involved in a plethora of plant growth and stress responses, global identification of TZF1 mRNA targets and cognate recognition motifs will help establish predictive models for TZF family protein-mediated RNA regulation in other plant species. Therefore, this project will reveal the mechanisms by which P-body modulates mRNA regulation, and contribute to a general understanding of stress signaling, particularly via intricate interfacing with post-transcriptional and translational regulatory network.
This award was co-funded by the Cellular Dynamics and Function and Genetic Mechanisms clusters of the Division of Molecular and Cellular Biosciences.
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.
