variant of RING finger, HC subclass, found in interferon regulatory factor 2-binding protein 1 (IRF-2BP1)
IRF-2BP1, also known as IRF-2-binding protein 1, is a nuclear protein that binds to the C-terminal repression domain of IRF-2 and acts as an IRF-2-dependent transcriptional corepressor, both enhancer-activated and basal transcription. It binds to Jun-dimerization protein 2 (JDP2), a member of the activating protein-1 (AP-1) family of transcription factors, and enhances the polyubiquitination of JDP2. It also represses activating transcription factor-2 (ATF2)-mediated transcriptional activation from a cyclic AMP-responsive element (CRE)-containing promoter. IRF-2BP1 contains an N-terminal C4-type zinc finger and a C-terminal variant C3HC4-type RING-HC finger.
Comment:based on the structure of Homo sapiens IRF-2BPL with bound Zn2+ ions through its variant RING-HC finger
Comment:typical 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.
Comment:The C3HC4-type RING-HC finger of Homo sapiens IRF-2BPL shows a partially new pattern by comparing with the typical C3HC4-type RING-HC finger. The third, sixth and seventh conserved Cys residues are in different positions.
Jiyao W et al.(2023). "The conserved domain database in 2023.",