title: Localization of histidyl-tRNA synthetase (Jo-1) in human laryngeal epithelial carcinoma cell line (HEp-2 cells).
abstract: The present study was designed to determine the subcellular localization of histidyl-tRNA synthetase (Jo-1) in human laryngeal epithelial carcinoma cell line (HEp-2 cells). Indirect immunofluorescence using commercial HEp-2 cells with human serum and human-affinity-purified anti-Jo-1 antibodies was performed using confocal microscopy. Anti-histidyl-tRNA-synthetase-positive sera showed distinct nuclear and cytoplasmic granular staining in HEp-2 cells. Affinity purified anti-Jo-1 produced an identical pattern to the whole serum, whereas the serum fraction that did not bind to the affinity column was negative by immunofluorescence on HEp-2 cells. Two commercial human anti-Jo-1-positive control sera and seven anti-Jo-1-positive sera from patients with myositis reproduced the nuclear and cytoplasmic granular pattern. We conclude that Jo-1 is present in cytoplasm and in intact nuclei from HEp-2 cells. The presence of tRNA synthetases in intact nuclei suggests that they have an unsuspected function in the nucleus.
authors.affiliation: Division of Rheumatic Diseases, Department of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA. vazquez@panda.uchc.edu
authors.forename: D
authors.initials: D
authors.lastname: Vázquez-Abad
authors.forename: J H
authors.initials: JH
authors.lastname: Carson
authors.forename: N
authors.initials: N
authors.lastname: Rothfield
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D006367:HeLa Cells; D006643:Histidine-tRNA Ligase / Q000378:metabolism*; D006801:Humans; D007822:Laryngeal Neoplasms / Q000473:pathology; D009220:Myositis / Q000097:blood / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D006643:Histidine-tRNA Ligase