Figure 2.

Circadian Oscillator model (Model B) with miRNA regulation. The model incorporates gene transcription, transport of mRNA (M_P) into the cytosol where it is translated into the clock protein (P₀) and degraded. The clock protein can be reversibly phosphorylated from the form P₀ into the forms P₁ and P₂, successively. The latter form is degraded or transported into the nucleus (P_N), where it exerts a negative feedback of cooperative nature on the expression of its gene. The model accounts for circadian oscillations of Per mRNA and corresponding protein in Drosophila. Details of the model are available in [20] and miRNA regulation is included in the model in a similar fashion as in Fig. 1