[Plants for Life Seminar] Coordination of the plant circadian clock at the single cell level

Title: Coordination of the plant circadian clock at the single cell level

Speaker: James Locke

Affiliation: Sainsbury Laboratory, University of Cambridge, Cambridge, UK

Abstract: The Arabidopsis circadian clock controls processes through the day and night. Through a combination of experiment and mathematical modelling, a multiple feedback loop circuit has been shown to generate this 24-hr rhythm. However, to really understand how clock rhythms are coordinated across the plant, we must examine the rhythm in single cells. To do this, we have examined reporters for clock activity at the single cell level across Arabidopsis seedlings over several days under constant environmental conditions. Our data reveal robust single cell oscillations, albeit desynchronised. In particular, we observe two waves of clock activity; one going down, and one up the root. We also find evidence of cell-to-cell coupling of the clock, especially in the root tip. A simple model shows that cell-to-cell coupling and our measured period differences between cells can generate the observed waves. Our results show how a combination of mathematical modelling and single cell time-lapse microscopy can reveal the spatial structure of the plant clock.