Aminoacyl-tRNA synthetases catalyze the aminoacylation of
tRNA by their cognate amino acid. Because of their central role in
linking amino acids with nucleotide triplets contained in tRNAs,
aminoacyl-tRNA synthetases are thought to be among the first
proteins that appeared in evolution. Two forms of tryptophanyl-tRNA
synthetase exist, a cytoplasmic form, named WARS, and a
mitochondrial form, named WARS2. Tryptophanyl-tRNA synthetase
(WARS) catalyzes the aminoacylation of tRNA(trp) with tryptophan
and is induced by interferon. Tryptophanyl-tRNA synthetase belongs
to the class I tRNA synthetase family. Four transcript variants
encoding two different isoforms have been found for this gene.
