| Type: | Domain | Name: | R3H domain |
| Description: | The R3H domain is a conserved sequence motif found in proteins from a diverse range of organisms including eubacteria, green plants, fungi and variousgroups of metazoans, but not in archaea and Escherichia coli. The R3H domain contains an invariant arginine and a highly conserved histidine, that areseparated by three residues. It also displays a conserved pattern of hydrophobic residues, prolines and glycines. It can be found alone, inassociation with AAA domain or with various DNA/RNA binding domains like DSRM, KH, G-patch, PHD, DEADbox, or RRM. The functions of these domains indicate that the R3H domain might be involved in polynucleotide-binding, including DNA, RNA and single-stranded DNA [].The 3D structure of the R3H domain has been solved. The fold presents a small motif, consisting of a three-stranded antiparallel beta-sheet, against which two alpha-helices pack from one side. This fold is related to the structures of the YhhP protein and the C-terminal domain of thetranslational initiation factor IF3. Three conserved basic residues cluster on the same face of the R3H domain and could play a role in nucleic acidrecognition. An extended hydrophobic area at a different site of the molecular surface could act as a protein-binding site []. | Short Name: | R3H_dom |
