Mapping of the immunophilin-immunosuppressant site of interaction on calcineurin

Husi, H., Luyten, M. A. and Zurini, M. G.M. (1994) Mapping of the immunophilin-immunosuppressant site of interaction on calcineurin. Journal of Biological Chemistry, 269(19), pp. 14199-14204. (PMID:7514602)

Abstract

The interaction of the immunosuppressive complexes cyclosporin A-cyclophilin A and FK506 binding protein-FK506 with the Ca(2+)- and calmodulin-dependent protein phosphatase calcineurin has been investigated by means of photoaffinity labeling and chemical cross-linking. Photolabeling of purified bovine brain calcineurin with the affinity label [O-[4-[4-(1-diazo-2,2,2-trifluoroethyl)benzoyl]aminobutanoyl]-D- serine8]cyclosporin in the presence of cyclophilin A results, in addition to the labeling of cyclophilin itself, in the transfer of some of the chemical probe to both the catalytic subunit A and the regulatory subunit B of calcineurin. Chemical cross-linking studies with disuccinimidyl suberate in the presence of either cyclophilin A, B, or C in complex with cyclosporin A or FK506 binding protein-FK506 result on the other hand in the apparently exclusive and strictly immunosuppressant-dependent formation of covalent immunophilin-calcineurin B subunit products. Cross-linking of immunophilins to calcineurin B subunit requires the presence of subunit A. In the present study, using a set of recombinant maltose-binding protein fusion products representing different stretches of the catalytic subunit A, we were able to map the minimal calcineurin A sequence necessary for immunophilin-ligand-calcineurin B interaction to occur.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Husi, Dr Holger
• Authors: Husi, H., Luyten, M. A., and Zurini, M. G.M.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health
• Journal Name: Journal of Biological Chemistry
• Publisher: American Society for Biochemistry and Molecular Biology, Inc.
• ISSN: 0021-9258