Mechanisms for coexistence of two limit cycles in a biochemical model
Résumé
Recently, a differential model of the p53-Mdm2 biochemical network which shows birhythmicity has been proposed to reproduce the two experimentally observed frequencies of oscillations of p53. We analyze the mechanisms at the origin of this birhythmic behaviour. Our approach is to approximate this continuous non-linear model into a lower dimensional piecewise affine model. We build the first return map to show the occurrence of two stable coexistent limit cycles.