This entry represents the central region of the E3 ubiquitin-protein ligase RNF220 []. RNF220 also interacts with beta-catenin independently of its E3 ligase activity; instead of ubiquitinating and destabilising it, RNF220 promotes beta-catenin stabilisation and canonical Wnt signaling []. Proteins containing this domain also include Drosophila Tey protein and some uncharacterised fungal proteins. Tey (Teyrha-Meyhra) is a transcription factor that suppresses Toll expression [].
RNF220 is an E3 ubiquitin-protein ligase that promotes the ubiquitination and proteasomal degradation of Sin3B, a scaffold protein of the Sin3/HDAC (histone deacetylase) corepressor complex. It can also bind E2 and mediate auto-ubiquitination of itself. Moreover, RNF220 specifically interacts with beta-catenin, and enhances canonical Wnt signaling through ubiquitin-specific protease 7 (USP7)-mediated deubiquitination and stabilization of beta-catenin, which is independent of its E3 ligase activity. RNF220 contains a characteristic C3HC4-type RING-HC finger at its C terminus [, ].
