P53
P53 is a tumour suppressor gene, which is accumulates when DNA becomes damaged beyond repair or the cell becomes stressed [1]. In a normal cell in which DNA is not damaged or when the cell is not stressed, Mdm2 binds to P53. Mdm2 is a polyubiquitin ligase which labels P53 for degredation. However, when DNA is damaged, or when the cell is stressed, ATM becomes activated which phosporylates P53 preventing the binding of Mdm2 [2] . Consequently the levels of P53 increase, inducing the production of p21 resulting in the inhibition Cdk-Cyclin complexs which arrest the cell division cycle [3] . However if P53 levels increase to a high level due to high levels of DNA damage, apoptosis results.
Cancer cells accumulate more mutations due to the loss of P53 which allows the cell division cycle to progress even when DNA is damaged [4] . P53 has also been recognised to be effective in treatment against cancers, neurodegeneration, ischemia, cholesatasis and atherosclerosis; this is proven by the fact that defective P53 treatment causes these disease states. Treatment involves P53 switched on again for tumour treatment [5].
References
- ↑ Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, Peter Walter, (2008) Molecular Biology of the Cell, 5th edition, New York: Garland Science p.1123
- ↑ Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, Peter Walter, (2008) Molecular Biology of the Cell, 5th edition, New York: Garland Science p.1105
- ↑ Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, Peter Walter, (2008) Molecular Biology of the Cell, 5th edition, New York: Garland Science p.1105-1107
- ↑ Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, Peter Walter, (2008) Molecular Biology of the Cell, 5th edition, New York: Garland Science p.1106
- ↑ Amaral JD, Xavier JM, Steer CJ, Rodrigues CM, 2010, Targeting the p53 pathway of apoptosis, Curr Pharm Des, 16(22), 2493-503.