InterPro domain: IPR000738

A conserved domain of 46 amino acids, called WHEP-TRS has been shown [ 1 ] to exist in a number of higher eukaryote aminoacyl-transfer RNA synthetases. This domain is present one to six times in the several enzymes. There are three copies in mammalian multifunctional aminoacyl-tRNA synthetase in a region that separates the N-terminal glutamyl-tRNA synthetase domain from the C-terminal prolyl-tRNA synthetase domain, and six copies in the intercatalytic region of the Drosophila enzyme. The domain is found at the N-terminal extremity of the mammalian tryptophanyl-tRNA synthetase and histidyl-tRNA synthetase, and the mammalian, insect, nematode and plant glycyl-tRNA synthetases [ 2 ]. The structure of a human WHEP-TRS domain has been solved and consists of two helices arranged in a helix-turn-helix [ 3 ]. The WHEP-TRS domain may play a role in the association of tRNA-synthetases into multienzyme complexes [ 4 ].

1. A component of the multisynthetase complex is a multifunctional aminoacyl-tRNA synthetase. EMBO J. 10, 4267-77
2. Primary structure of the gene for glycyl-tRNA synthetase from Bombyx mori. J. Biol. Chem. 268, 7660-7
3. Structural analysis of multifunctional peptide motifs in human bifunctional tRNA synthetase: identification of RNA-binding residues and functional implications for tandem repeats. Biochemistry 39, 15775-82
4. A multifunctional repeated motif is present in human bifunctional tRNA synthetase. J. Biol. Chem. 273, 11267-73