Prof. Nick FoulkesCircadian Clock Biology
Using fish as a model system to study the vertebrate circadian clock.
Almost every aspect of plant and animal biology shows day - night rhythms. Many persist even under constant conditions however with period lengths that are not precisely 24 hours and for this reason they are termed „circadian“ (Circa – diem, approximately one day). Central to the generation of circadian rhythms is an endogenous circadian clock which is constantly reset ("entrained") by environmental factors such as light to ensure that it remains synchronised with the natural 24-hour cycle.
The past few decades have seen a considerable advance in our understanding of the mechanisms and regulation of the circadian clock. However, comparatively little is known about the plasticity of these systems and how evolution has shaped their current form. Knowledge of these fundamental processes is essential for gaining a complete understanding of the dynamic properties of biological systems. Our laboratory aims to address this issue by comparing the regulation and function of the circadian clock in a wide range of animal models occupying diverse environments.
We study animal models, notably fish species, that have evolved in diverse environments and that consequently show fundamental differences in the regulation and function of their circadian timing systems. In particular, we focus on genetically accessible model species such as the zebrafish as well as fish that occupy extreme habitats such as blind cavefish. We study and compare the mechanisms which regulate their circadian clocks in response to sunlight and feeding as well as how their clocks control the timing of DNA repair and the cell cycle.