Transition graph of the model of p53 response to DNA damage. Transition graph of the p53 model (generated by GINsim). The node states should be read as [p53 Mdm2C Mdm2N Dam] = [∗∗∗∗] (where ∗can be either 0 or 1). For instance, [p53 Mdm2C Mdm2N Dam]= corresponds to a state in which only p53 (at its level 1) is active. The nodes in green and the nodes in light blue belong to two cycles, the node in red is the fixed point and the other nodes are in dark blue.