Anti-histidyl-tRNA synthetase 1 antibodies are used for the immunodetection of the protein encoded by the HARS1 gene. In humans, the canonical protein has a reported length of 509 amino acid residues and a mass of 57.4 kDa. Its subcellular localization is in the cytoplasm. Alternative splicing is reported to yield 4 different isoforms for this protein. A member of the Class-II aminoacyl-tRNA synthetase protein family, it is known to catalyze the ATP-dependent ligation of histidine to the 3'-end of its cognate tRNA, via the formation of an aminoacyl-adenylate intermediate (His-AMP). The gene encoding this protein is implicated in Usher syndrome. Other names for this target antigen include HARS, HRS, USH3B, histidine--tRNA ligase, cytoplasmic, HisRS, Jo-1 antigen, histidine translase, and CMT2W. Gene orthologs have been identified in the mouse, rat, bovine, zebrafish, chimpanzee and chicken species.