UBIQUITIN, E6-AP, AND THEIR ROLE IN P53 INACTIVATION

Inactivation of the tumor suppressor protein p53 Flays a key role in h uman carcinogenesis. Activation of the growth suppressive properties o f p53 by appropriate stress signals, including genotoxic stress, is ge nerally accompanied by intracellular accumulation of the protein. This suggests that stabilization of the otherwise short-lived protein is a n intrinsic feature of p53 activation. The ubiquitin/proteasome system is believed to be a major proteolytic system involved in selective de gradation of cell regulatory proteins. In this review, the potential r ole of the ubiquitin/proteasome system in p53 degradation and possible mechanisms involved in p53 stability regulation are discussed. (C) 19 98 Elsevier Science Inc.