Most organisms live in environmental conditions that oscillate with a 24 hour period and evolved an endogenous mechanism, known as the circadian clock, which coordinates the temporal organization of biological processes to optimal times of the day or night. Biological clocks allows an organism to anticipate the onset of periodic environmental changes providing an adaptive advantage that results in increased fitness and survival.
In plants, the pervasiveness of the clock control extends to nearly every aspect of growth and development through an extensive transcriptional regulatory network that impose circadian oscillations to more than one third of the whole transcriptome.
My laboratory is focused in studying the molecular mechanisms by which the circadian clock controls critical biological processes (i.e. outputs). In particular, we use plant-pathogen interactions as an experimental platform and aim to understand the transcriptional networks that control the circadian regulation of plant defense responses. Host-pathogen interactions are regulated by sophisticated mechanisms shaped by millions of years of coevolution. In fact, immune responses are regulated by the circadian clock not only in plants but also in other organisms such as flies and mice, suggesting that this is an evolutionary advantageous mechanism. Since the clock function and plant-pathogen responses are largely dependent on the regulation of gene expression, an extensive transcriptional network is anticipated at the interface of clock and defense signaling pathways. Using forward and reverse genetics, as well as systems approaches, we are primarily focused on identifying critical components of these transcriptional regulatory networks.
Plant pests account for great losses in crop yield around the world, thus our findings may ultimately transform our understanding of plant microbial infections and how to treat them. Moreover, plant research made major impact in understanding critical mechanisms of great biological and biomedical relevance including RNA-silencing, DNA-methylation, proteasomal-control of protein stability and programmed cell death among others. Therefore, our research could potentially uncover highly conserved regulatory networks orchestrating immune defenses in other organisms as well.
Dr. Pruneda-Paz received his Ph.D. in Biochemistry from the National University of Cordoba (Argentina), and carried out his postdoctoral research at The Scripps Research Institute and the University of California, San Diego.