The fidelity of protein synthesis requires efficient discrimination of amino acid substrates by aminoacyl-tRNA synthetases. Aminoacyl-tRNA synthetases function to catalyze the aminoacylation of tRNAs by their corresponding amino acids, thus linking amino acids with tRNA-contained nucleotide triplets. GluRS (glutamyl-tRNA synthetase 2), also known as EARS2 or MSE1, is a 523 amino acid protein that localizes to the mitochondrial matrix and belongs to the class I aminoacyl-tRNA synthetase family. Participating in protein biosynthesis, GluRS functions to catalyze the ATP-dependent attachment of glutamate to tRNA(Glu), a two-step reaction that involves the ATP-dependent activation of glutamate to form Glu-AMP and the subsequent transfer of the glutamate residue to tRNA(Glu).