Constitutive and induced functions of the p53 gene

The p53 tumor suppressor serves to secure genetic stability of multicellular organisms. It suppresses the accumulation of mutations in somatic cells and substantially decreases the probability of malignant diseases. The p53 gene acts highly selectively through multiple mechanisms. Under relatively favorable conditions, p53 helps to maintain intracellular homeostasis by balancing anabolic and catabolic processes and by timely elimination of reactive oxygen species. These functions of p53 facilitate maximal efficiency and survival of cells under conditions of physiological stresses. In the case of grave molecular damage caused by severe stress, a significant amount of highly active p53 is induced leading to irreversible growth arrest and programmed cell death. The induced functions of p53 secure the timely elimination from the organism of damaged and potentially dangerous cells. Collectively, the functions of p53 contribute to the prevention of malignant and other diseases and decelerate the aging process.