Q05086

UBE3A also known as E6-AP is an E3 ubiquitin-protein ligase, part of the ubiquitin protein degradation system. UBE3A plays a crucial role in the ubiquitin-proteasome pathway, which is essential for regulating protein degradation and maintaining cellular homeostasis. UBE3A is primarily located in the nucleus and cytoplasm, where UBE3A facilitates the ubiquitination of target proteins, thereby marking them for degradation by the 26S proteasome. Proper localization of UBE3A is vital, as UBE3A ensures that substrates such as the tumor suppressor protein p53 are effectively regulated; dysregulation can lead to the accumulation of p53 in the cytoplasm, contributing to oncogenic processes and disorders like Angelman syndrome. UBE3A′s interaction with the human papillomavirus E6 oncogene further underscores UBE3A′s importance in cancer biology, as this interaction enhances the ubiquitination of p53, promoting its degradation and allowing for unchecked cellular proliferation.