YARS

Tyrosyl-tRNA synthetase, cytoplasmic, also known as Tyrosine-tRNA ligase, is an enzyme that in humans is encoded by the YARS gene.

Aminoacyl-tRNA synthetases catalyze the aminoacylation of transfer RNA (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. Tyrosyl-tRNA synthetase belongs to the class I tRNA synthetase family. Cytokine activities have also been observed for the human tyrosyl-tRNA synthetase, after it is split into two parts, an N-terminal fragment that harbors the catalytic site and a C-terminal fragment found only in the mammalian enzyme. The N-terminal fragment is an interleukin-8-like cytokine, whereas the released C-terminal fragment is an EMAP II-like cytokine. Recently, tyrosyl-tRNA synthetase has been demonstrated as the biologically and functionally significant target for resveratrol

For a comparison of cytoplasmic human tyrosyl-tRNA synthetase with its mitochondrial counterpart and with tyrosyl-tRNA synthetases of other biological kingdoms and organisms, see the Wikipedia page on Tyrosine-tRNA ligase and a general review on their structures and functions.