FKBP52 Antibody: RPE

HSP90 is crucial to cellular signaling by its regulation of the folding, activity, and stability of a wide range of client proteins. These client protein complexes may also contain one or more cochaperones (1). One class of HSP90-binding cochaperone is composed of proteins with a characteristic tetratricopeptide repeat (TPR) domain that forms an HSP90 binding site. Among the TPR cochaperones of HSP90 are Hop/Sti1, protein phosphatase PP5, and members of both the FK506- and cyclosporin A-binding families of immunophilins (2). FK506-binding protein 51 (FKBP51) and FKBP52 are large molecular weight immunophilins that are part of the mature glucocorticoid receptor (GR) heterocomplex (3). The N terminal domain of each protein binds FK506 and has peptidyl-prolyl isomerase (PPIase) activity that converts prolyl peptide bonds within target proteins from cis- to trans- proline. The C-terminal domains contain the TPR repeats involved in protein-protein interactions with the HSP90 (4). Although FKBP52 and FKBP51 share ~75% sequence similarity, they affect hormone binding by glucocorticoid receptor in opposing manners and have different HSP90-binding characteristics (3). FK506 binding protein 51 kDa (FKBP51 or otherwise referred to as FKBP54) has been identified as a progestininducible gene. This protein is predominantly expressed in murine T cells but in humans, it is abundantly expressed in numerous tissues at levels many times higher than FKBP12. The FKBP51 gene is known to be induced by glucocorticoids (5).

FK506 binding protein 4 Antibody, FKBP4 Antibody, FKBP59 Antibody, HBI Antibody, HSP56 Antibody, p52 Antibody, p59 Antibody, PPIase Antibody, Rotamase Antibody, T cell FK506 binding protein Antibody

0.5 µg/ml was sufficient for detection of FKBP52 in 20 µg total protein using WB by colorimetric immunoblot analysis using Goat Anti-Mouse IgG:HRP as the secondary.

1. Cheung-Flynn J., Roberts P.J., Riggs D.L., and Smith D.F. (2003) J. Biol. Chem. 278(19): 17388-17394. 2. Davies T.H., Ning Y.N., and Sanchez E.R. (2002) J Biol. Chem. 277 (7): 4597-4600. 3. Wu, B. et al. (2004) Proc. Natl. Acad. Sci. USA. 101(22): 8348-8353. 4. Denny W.B., Prapapanich V., Smith D.F., and Scammell J.G. (2005) Endocrinology 146(7):3194-3201. 5. Cox M.B. et al. (2007) Molecular Endocrinology. Epub.