Wiktionary
autoubiquitination
n. (context biochemistry English) Self-ubiquitination by an ubiquitinating enzyme, usually an E3 or E4 ubiquitin ligase. This activity can be direct, as in monoubiquitin of a lysine residue on the E3 or E4 itself, or indirect, through addition of ubiquitin to an existing polyubiquitin chain that is attached to the E3 or E4.