UbcH7/UBE2L3 Protein, Human

UbcH7/UBE2L3, a ubiquitin-conjugating enzyme E2, exhibits specificity in collaboration with HECT-type and RBR family E3 ubiquitin-protein ligases. Notably, its unique characteristic is the absence of intrinsic E3-independent reactivity with lysine, rendering it incompatible with most RING-containing E3 ubiquitin-protein ligases. However, it demonstrates activity with RBR family E3 enzymes such as PRKN, RNF31, and ARIH1, functioning akin to RING-HECT hybrids. Acting downstream of the E1 complex, UbcH7 catalyzes the covalent attachment of ubiquitin to target proteins and, in vitro, facilitates 'Lys-11'-linked polyubiquitination. Its involvement in the selective degradation of short-lived and aberrant proteins highlights its role in cellular quality control. Additionally, down-regulation during the S-phase suggests a contribution to cell cycle progression, while its impact on nuclear hormone receptors' transcriptional activity and potential role in myelopoiesis further underscore its multifaceted functions.