UBC20 (ubiquitin-conjugating enzyme 20); ubiquitin-protein ligase; Encodes one of two ubiquitin-conjugating enzymes belonging to the E2-C gene family (the other being UBC19). Transcript is always found in diving cells, but also in other non-dividing cells. ; Catalyzes the covalent attachment of ubiquitin to other proteins (180 aa)