Describe the p53/MDM2/P14RAF pathway in healthy cells

When no DNA damage is present p53 remains unphosphorylated, this allows it to bind to the MDM2 promoter reigon, stimulating the MDM2 expression. MDM2 regulates the levels of p53 in the cell, by binding with it to create an MDM2/p53 complex leading to p53 degredation.