RING finger, HC subclass, found in RING finger protein 40 (RNF40)
RNF40, also known as BRE1B or 95 kDa retinoblastoma-associated protein (RBP95), was identified as a novel leucine zipper retinoblastoma protein (pRb)-associated protein that may function as a regulation factor in RNA polymerase II-mediated transcription and/or transcriptional processing. RNF40 also functions as an E3 ubiquitin-protein ligase that forms a heterodimeric complex with BRE1B, also known as RNF40, to facilitate the K120 monoubiquitination of histone H2B (H2Bub1), a DNA damage-induced histone modification that is crucial for recruitment of the chromatin remodeler SNF2h to DNA double-strand break (DSB) damage sites. It cooperates with SUPT16H to induce dynamic changes in chromatin structure during DSB repair. RNF40 contains a C3HC4-type RING-HC finger at the C-terminus.
Comment:C3HC4-type RING-HC finger consensus motif: C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C, where X is any amino acid and the number of X residues varies in different fingers
Comment:A RING finger typically binds two zinc atoms, with its Cys and/or His side chains in a unique "cross-brace" arrangement.
Jiyao W et al.(2023). "The conserved domain database in 2023.",