Ubiquitination factor E4B (UBE4B)

Ubiquitination factor E4B (UBE4B) is a multifunctional **E3/E4 ubiquitin ligase** in the U-box protein family, encoded by the UBE4B gene. It catalyzes the transfer and extension of ubiquitin chains on target proteins, often in collaboration with E1 and E2 enzymes, and is essential in multiubiquitin chain assembly and proteasome-mediated degradation of abnormal, short-lived, or damaged proteins[1][3][5]. UBE4B plays critical roles in cellular processes such as DNA double-strand break repair, apoptosis, p53 regulation, protein quality control, neurodevelopment, and autophagy (including Tau clearance in neurons)[1][2][3][6]. UBE4B is implicated as an oncogene in various cancers due to its ability to regulate p53 stability and activity and has tumor suppressor roles in neuroblastoma where its loss is observed. Modulation of UBE4B function is being explored as a potential therapeutic strategy in both cancer and neurodegenerative disorders[2][3][5][6].

Other names

Ubiquitin conjugation factor E4 BHDNB1KIAA0684UBOX3E4UFD2UFD2AHomozygously deleted in neuroblastoma 1RING-type E3 ubiquitin transferase E4 BUbiquitin fusion degradation protein 2Homologous to yeast UFD2

Drugs that would target UBE4B would likely act by inhibiting its E3/E4 ubiquitin ligase activity, stabilizing tumor suppressors like p53 or altering protein degradation pathways in disease contexts[3]