F-box only protein 3 (FBXO3) is a substrate recognition component of the SCF (SKP1-CUL1-F-box protein)-type E3 ubiquitin ligase complex that mediates the ubiquitination of transcription factor coactivators such as HIPK2 and EP300, leading to their rapid degradation by the proteasome []. FBX03 interacts with a nuclear protein PML, which stabilises the transcription factor complex by protecting HIPK2 and p300 from SCFFbx3-induced degradation until transcription is completed []. PML, HIPK2 and FBXO3 may act synergically to activate p53/TP53-dependent transactivation [].
