Ubiquitin-conjugating enzyme E2 O (UBE2O)

Ubiquitin-conjugating enzyme E2 O (UBE2O) is a large, multifunctional enzyme with both E2 ubiquitin-conjugating activity and E3 ubiquitin ligase activity, classified as an E2/E3 hybrid. It is unique among ubiquitin system enzymes in that it can directly recognize diverse client proteins—especially unassembled ("orphan") and ribosomal proteins—for ubiquitination without requiring a separate E3 ligase, leading to targeted protein degradation by the proteasome[1][2][6]. UBE2O is critical for cellular protein quality control and remodeling, with a major role in terminal erythroid differentiation where it facilitates elimination of cellular components as hemoglobin accumulates[1][3][5][6]. UBE2O's action is regulated by cofactors such as NAP1L1, and dysfunction in its pathway results in anemia due to impaired ribosome elimination during reticulocyte maturation. Recent findings implicate UBE2O in cancer biology, neurodegeneration, and cellular stress responses, with its expression and function potentially relevant for biomarker development and therapeutic targeting[1][4][5].

Other names

E2-230KKIAA1734Ubiquitin carrier protein OE2/E3 hybrid ubiquitin-protein ligase UBE2Oubiquitin-protein ligase OE3-independent E2 ubiquitin-conjugating enzymeubiquitin conjugating enzyme E2OUbiquitin-conjugating enzyme E2 of 230 kDa

Inhibition or modification of ubiquitin-conjugating/ligase activity affecting protein turnover; Modulation of proteome remodeling in erythroid cells; Regulation of client selection and ubiquitination via interactions with NAP1L1