Modified RING finger, HC subclass (C3HC3D-type), found in Roquin-1, Roquin-2, and similar proteins
The ROQUIN family includes Roquin-1, Roquin-2, and similar proteins, which localize to the cytoplasm and upon stress, are concentrated in stress granules. They may play essential roles in preventing T-cell-mediated autoimmune disease and in microRNA-mediated repression of inducible costimulator (Icos) mRNA. They function as E3 ubiquitin ligases consisting of an N-terminal modified C3HC3D-type RING-HC finger with a potential E3 activity, a highly conserved ROQ domain required for RNA binding and localization to stress granules, and a CCCH-type zinc finger involved in RNA recognition.
Conserved feature residue pattern:C C C H C C C [DE]
Evidence:
Structure:4TXA; Mus musculus Roquin binds two Zn2+ ions, contacts at 4A. - View structure with Cn3D
Comment:modified RING-HC finger (C3HC3D-type)
Comment:consensus of the typical C3HC4-type RING-HC finger: C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C, 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.",