Study Reveals New Details Of Tumour Suppressor Gene P3 Regulation
The p53 protein is an important tumour suppressor protein which safeguards the cells from cancer. p53 constantly monitors the integrity of DNA molecules, and when defects are found it either corrects the errors, or destroys the cell (Richards, 2007). This protein repairs cells by binding to a gene to promote the transcription of another protein, p21. P21 enters the cell’s metabolism and shuts down the cell cycle at G1, allowing time for the DNA to be prepared before it is replicated during S phase (Richards 2007), slowing down the progression towards cancer. When repair is not possible, p53 stimulates the cell to enter into a pathway leading to programmed cell death (apoptosis). However, p53 is easily mutated and can function as an oncogene. The mutated p53 protein has an abnormal structure and cannot function. Therefore, the DNA structure is no longer monitored, mutations accumulate, checks and balances on the cell cycle can fail to operate, and cell growth proceeds unchecked (Richards 2007).
The results of a study at the Wistar Institute show that the p53 tumour suppressor is so vital in controlling cancer that its dysfunction is linked to more than half of human cancers (Richards 2007). It’s capacity for shutting down cell growth, even stimulating cell death means that it must be tightly regulated to maintain the optimal balance between protecting against cancer and permitting normal growth (Richards 2007).
These findings are significant in showing how regulatory mechanisms are crucial for cellular survival. Significant progress is being made in understanding how p53 regulation occurs, and how it might possibly be manipulated in the treatment of cancer.
The attached image shows the p53 gene and its related protein.
References:
Richards 2007, Study Reveals New Details of Tumour Suppressor Gene P53 Regulation, viewed 22 March 2009, from www.newhopeblog.com/.../09/study_reveals_n.php
