E3 ubiquitin-protein ligase that accepts ubiquitin from the E2 ubiquitin-conjugating enzyme UBE2D1 in the form of a thioester and then directly transfers the ubiquitin to targeted substrates. UBE3C can assemble unanchored poly-ubiquitin chains in either 'Lys-29'- or 'Lys-48'-linked polyubiquitin chains. It has preference for 'Lys-48' linkages. It can target itself for ubiquitination in vitro and may promote its own degradation in vivo. Protein Interaction Partner: UBC, GOLGA2, PSMD14, SHFM1, UBE2D1, PSMD2, PSMC5, PANK4, EEF2K, WDR92, TLK1, MTA2, ECT2, CPEB4, THOC7, RBM15, THOC2, WDR74, KDM1A, USP13, UTRN, PHKA2, APP, UBE2L3, UBE3C, PSMA2, ELAVL1, RAD21, MYC, CAND2, PSMD6, Protein Size: 404