CBLL1, also known as HAKAI (meaning ‘destruction’ in Japanese), or RNF188 (RING finger protein 188), is a 491 amino acid protein that contains one C2H2-type zinc finger and one RING-type zinc finger. CBLL1 is believed to function as an E3 ubiquitin-protein ligase that accepts a ubiquitin residue from an E2 ubiquitin-conjugating enzyme and immediately transfers that residue to a protein that is targeted for degradation. More specifically, upon activation of c-Src, CBLL1 interacts with and ubiquitinates tyrosine-phosphorylated E-cadherin, thereby targeting the E-cadherin complex for endocytosis and disrupting epithelial cell-cell contacts. Via its role as an E-cadherin regulator, CBLL1 participates in cell adhesion and may also be involved in the regulation of epithelial-mesenchymal transitions.