A Death-Survival Switch in Cell: Cross Talk between Akt and p53

A dynamical model for the p53-Mdm2 feedback loop regulated by Akt is reported in this work. By computational simulation, it reproduces the stable oscillatory pulses in p53- Mdm2 negative feedback loop which is functionally responsible for cell repair or apoptosis in individual cell. With the survival stress, in the tumor suppressor-oncoproteins networks, the model indicates the potential to exhibit the oscillation-stationary state bifurcation for the kinetics of p53, and the death-survival switch in the p53-Akt cross talk which somehow leads cell to either programmed apoptosis or survival. It´s found that low Akt activation is speculated to p53 normally holding the response to cellular repair or apoptosis, but large Akt amount keeping a high Akt activation restricts p53 at a low expression level and engenders malfunctions in cellular repair or apoptosis so that the cell survives with potential probability to cancer or mutation.