  Recent studies suggest that PML (Promyelocytic Leukemia) suppresses p53
protein degradation by inhibiting MDM2 protein in the nucleus [1], and
regulates a number of biological functions [2]. We modeled a PML-MDM2-p53
regulatory network by integrating p53-MDM2 autoregulatory model [3] and related
PML pathways. We found that p53 dynamics switched at various dynamical states
induced by PML which corresponds to different cellular states. Our results show
clear transitions among the stabilized, damped and sustain states under
different stress conditions induced by PML in the system. These states in p53
dynamics is the signature of existence of various cellular states and the phase
transition like behaviour of these states involve various biological
significance.
