PRORP-like PIN domain of ribonuclease Zc3h12a and related proteins
Zc3h12a (zinc finger CCCH-type containing 12A, also known as MCPIP1/MCP induced protein 1 and Regnase-1) is a critical regulator of inflammatory response, with additional roles in defense against viruses and various stresses, cellular differentiation, and apoptosis. This subfamily also includes three less-studied mammalian homologs: Zc3h12b-d/Regnase-2-4. It belongs to the Zc3h12a-N4BP1-like PIN subfamily of the PRORP-Zc3h12a-like PIN family, the latter of which additionally includes human PRORP, also known as proteinaceous RNase P and mitochondrial RNase P protein subunit 3 (MRPP3), and Arabidopsis thaliana PRORP1-3. The PIN (PilT N terminus) domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its active center, consisting of three highly conserved catalytic residues which coordinate metal ions; in some members, additional metal coordinating residues can be found while some others lack several of these key catalytic residues. The PIN active site is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons.
Structure:3V34: Human MCPIP1 N-terminal PIN domain binds Mg2+
Comment:based on structure and experimental evidence from PIN-superfamily members belonging to the FEN-like, VapC-like, PRORP-like, and LabA-like families
Comment:The PIN domain superfamily contains three highly conserved catalytic residues which coordinate metal ions; in some members, additional metal coordinating residues can be found while some others lack several of these key catalytic residues. In this subgroup 5 conserved catalytic residues are found.