Polyubiquitination of the tumor suppressor p53 (encoded by TP53) regulates its stability by targeting it for degradation. Wu et al. now report that UBE4B, an E3 and E4 ligase, is a key enzyme in this process and that overexpression of UBE4B in some brain tumors is associated with reduced p53 abundance, suggesting a previously unknown mechanism blocking p53 function in cancer.
- Hong Wu
- Scott L Pomeroy
- Roger P Leng
