Fig. 1
From: Circadian oscillator proteins across the kingdoms of life: structural aspects
Generic model of the circadian clock. The complex network of coupled multiple feedback oscillators are represented by solid color lines and ovals. Clock genes forming a functional oscillator regulate the input and output pathways (blue dashed lines). Feedback from output pathways can also regulate the oscillator and the input pathways (red dashed lines). In addition to external input signal transduction for clock entrainment, input pathways can also directly affect clock output and vice versa (solid black line). The model is adapted from a model depicted in [3]