Tyrosyl-tRNA synthetase(YARS2) is a mitochondrial protein which catalyzes the attachment of tyrosine to tRNA(Tyr) in a two-step reaction: tyrosine is first activated by ATP to form Tyr-AMP and afterward transferred to the acceptor end of tRNA(Tyr). YARS2 gene mutations are linked with myopathy with lactic acidosis and sideroblastic anemia type 2(MLASA2).