Molecular Clocks and Light Signalling

The ability at the molecular level to keep track of time is a property shared by organisms ranging from the simplest unicells to humans. The primary feature of these biological clocks is their ability to entrain to environmental stimuli. The dominant stimulus comes from environmental light cues, which requires the existence of photopigments sensitive to light. The exact identity of the molecules involved in circadian photoreception has remained elusive. The classical view of the circadian system is of diverse physiological rhythms regulated by a centralized clock structure. This book presents evidence that challenges this view. Experiments in both vertebrate and invertebr…