Abstract
One of the most investigated and inscrutable eukaryotic proteins is a factor positioned as tumor suppressor which structural changes are observed in 50% of malignant cells. In the literature this protein is referred to as p53. The generalized function of p53 resolves to maintaining of cell genetic stability and preventing cell automatization. Therefore, p53 was called the keeper, or guardian, of the genome. Suppressive activity of p53 in regard to appearance of malignant cells seems to be side function of this protein. The present review prоvides data on the role of p53 in various vital processes in eukaryotic cells. p53 is a complex protein in its domain structure, and the semi-autonomous role of individual domains is clearly discernible. Normally, p53 is not a crucial factor in ontogenesis. At the same time p53 modulates the activity of about 500 different genes and also maintains homeostasis in cells and organism directly via protein-protein interactions. In response to exogenous and endogenous impacts p53 provides a balance of cellular metabolism and either promotes elimination of abnormalities, or triggers an apoptotic cascade. The review summarizes current considerations of p53 multiple functions as well as discusses already established and not yet disclosed mechanisms concerning involvement of said factor in cellular metabolism.