Tissue distribution and cellular localization of hsp56, an FK506-binding protein. Characterization using a highly specific polyclonal antibody

• Published in: The Journal of biological chemistry 1992-10, Vol.267 (30), p.21285-21288
• Main Authors: Ruff, V.A., Yem, A.W., Munns, P.L., Adams, L.D., Reardon, I.M., Deibel, M.R., Leach, K.L.
• Format: Article
• Language: English
• Subjects: Analytical, structural and metabolic biochemistry; Animals; Antibodies - immunology; Antibody Specificity; Biological and medical sciences; Carrier Proteins - immunology; Carrier Proteins - metabolism; Cells, Cultured; distribution; Electrophoresis, Gel, Two-Dimensional; FK506-binding protein; Fluorescent Antibody Technique; Fundamental and applied biological sciences. Psychology; Heat-Shock Proteins - immunology; Heat-Shock Proteins - metabolism; hsp56 protein; Humans; Jurkat cells; lymphocytes T; Male; man; Miscellaneous; Proteins; Rats; Rats, Sprague-Dawley; Tacrolimus - metabolism; Tacrolimus Binding Proteins; Tissue Distribution
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(19)36603-7

Heat shock protein 56 (hsp56) has been shown to be involved in two cellular pathways, as an immunophilin for FK506 and as a component of steroid receptor complexes. To help define its role in these cellular pathways, we have developed UPJ56, a polyclonal antibody raised against hsp56 purified from Jurkat cells. In Western blot experiments, hsp56 was highly expressed in rat thymus, liver, and spleen, with low levels in lung and muscle. In immunofluorescence experiments using untreated LLC-PK1 cells, fibrillar staining was seen in the cytoplasm, suggesting a cytoskeletal localization of hsp56. The nuclei were brightly stained, except for the nucleoli. Confocal microscopy demonstrated that the staining was present in all planes of the nucleus. These results suggest that hsp56 is expressed in tissues enriched in steroid receptors and is highly expressed in tissues involved in T cell function. Furthermore, the localization of hsp56 with the cytoskeleton and throughout the nucleus is consistent with its association with steroid receptor complexes.