RING finger, HC subclass, found in RING finger protein 169 (RNF169) and similar proteins
RNF169 is an uncharacterized E3 ubiquitin-protein ligase paralogous to RNF168. It functions as a negative regulator of the DNA damage signaling cascade. RNF169 recognizes polyubiquitin structures but does not itself contribute to double-strand break (DSB)-induced chromatin ubiquitylation. It contributes to regulation of the DSB repair pathway utilization via functionally competing with recruiting repair factors, 53BP1 and RAP80-BRCA1, for association with RNF168-modified chromatin independent of its catalytic activity, limiting the magnitude of the RNF8/RNF168-dependent signaling response to DSBs. RNF169 contains an N-terminal C3HC4-type RING-HC finger and a C-terminal MIU (motif interacting with ubiquitin) domain.