P53
P53 is a tumour suppressor gene, which accumulates when DNA is damaged beyond repair or the cell becomes stressed [1]. In a normal cell where DNA is not damaged or when the cell is not under stress, Mdm2 binds to P53. Mdm2 is a polyubiquitin ligase which labels P53 for degradation. However, when DNA is damaged or 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] . When P53 level increases to a high level due to extensive DNA damage, the cell will undergo apoptosis.
Cancer occurs due to the loss of P53 and thus, allows the cell division cycle to progress eventhough 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 gene contributes to the diseases. Treatment involves activating P53 gene 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.