How are dynamic gene circuits coupled together?
Coupling in the Cyanobacterial circadian clock. The circadian (24 hour) clock in cyanobacteria couples to multiple processes, including cell division, light, metabolism, and stress responses. We are attempting to unravel how the clock receives input from, and drives, such a wide range of processes robustly. For example, In collaboration with Dr. Philipp Thomas from Imperial, we have examined how the clock modulates cell size control by continuously regulating the division rate throughout the day. (Martins et al., 2018). We have also discovered how cells can double the frequency of the clock using an oscillatory feedforward loop (Martins et al. 2016).
Coupling in the Arabidopsis circadian clock. We examined clock activity at the single cell level across Arabidopsis seedlings over several days under constant environmental conditions (Gould et al., 2018). Our data revealed two waves of clock activity- one going down, and one up the root. We have then used modelling and experiment to predict and measure clock wave dynamics under a range of environmental conditions. We find that waves are generated by period differences between tissues and local cell to cell coupling (Greenwood et al., 2019).