The SWIB/MDM2 motif of UBE4B activates the p53 pathway

Autor: H. Helena Wu, Sarah Leng, Yasser Abuetabh, Consolato Sergi, David D. Eisenstat, Roger Leng
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Molecular Therapy: Nucleic Acids, Vol 31, Iss , Pp 466-481 (2023)
Druh dokumentu: article
ISSN: 2162-2531
DOI: 10.1016/j.omtn.2023.02.002
Popis: The tumor suppressor p53 plays a critical role in cancer pathogenesis, and regulation of p53 expression is essential for maintaining normal cell growth. UBE4B is an E3/E4 ubiquitin ligase involved in a negative-feedback loop with p53. UBE4B is required for Hdm2-mediated p53 polyubiquitination and degradation. Thus, targeting the p53-UBE4B interactions is a promising anticancer strategy for cancer therapy. In this study, we confirm that while the UBE4B U box does not bind to p53, it is essential for the degradation of p53 and acts in a dominant-negative manner, thereby stabilizing p53. C-terminal UBE4B mutants lose their ability to degrade p53. Notably, we identified one SWIB/Hdm2 motif of UBE4B that is vital for p53 binding. Furthermore, the novel UBE4B peptide activates p53 functions, including p53-dependent transactivation and growth inhibition, by blocking the p53-UBE4B interactions. Our findings indicate that targeting the p53-UBE4B interaction presents a novel approach for p53 activation therapy in cancer.
Databáze: Directory of Open Access Journals