Journal of Biosciences

, Volume 32, Supplement 1, pp 991–997 | Cite as

The p53-MDM2 network: from oscillations to apoptosis

  • Indrani Bose
  • Bhaswar Ghosh


The p53 protein is well-known for its tumour suppressor function. The p53-MDM2 negative feedback loop constitutes the core module of a network of regulatory interactions activated under cellular stress. In normal cells, the level of p53 proteins is kept low by MDM2, i.e. MDM2 negatively regulates the activity of p53. In the case of DNA damage, the p53-mediated pathways are activated leading to cell cycle arrest and repair of the DNA. If repair is not possible due to excessive damage, the p53-mediated apoptotic pathway is activated bringing about cell death. In this paper, we give an overview of our studies on the p53-MDM2 module and the associated pathways from a systems biology perspective. We discuss a number of key predictions, related to some specific aspects of cell cycle arrest and cell death, which could be tested in experiments.


Apoptosis cancer cell cycle MDM2 overexpression tumour suppressor 


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Copyright information

© Indian Academy of Sciences 2007

Authors and Affiliations

  1. 1.Department of PhysicsBose InstituteKolkataIndia

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