title: Redox regulation of cyclophilin A by glutathionylation.
abstract: Using redox proteomics techniques to characterize the thiol status of proteins in human T lymphocytes, we identified cyclophilin A (CypA) as a specifically oxidized protein early after mitogen activation. CypA is an abundantly expressed cytosolic protein, target of the immunosuppressive drug cyclosporin A (CsA), for which a variety of functions has been described. In this study, we could identify CypA as a protein undergoing glutathionylation in vivo. Using MALDI-MS we identified Cys52 and Cys62 as targets of glutathionylation in T lymphocytes, and, using bioinformatic tools, we defined the reasons for the susceptibility of these residues to the modification. In addition, we found by circular dichroism spectroscopy that glutathionylation has an important impact on the secondary structure of CypA. Finally, we suggest that glutathionylation of CypA may have biological implications and that CypA may play a key role in redox regulation of immunity.
authors.affiliation: Mario Negri Institute for Pharmacological Research, Milan, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Ghezzi
authors.forename: Simona
authors.initials: S
authors.lastname: Casagrande
authors.forename: Tania
authors.initials: T
authors.lastname: Massignan
authors.forename: Manuela
authors.initials: M
authors.lastname: Basso
authors.forename: Emanuele
authors.initials: E
authors.lastname: Bellacchio
authors.forename: Luca
authors.initials: L
authors.lastname: Mollica
authors.forename: Emiliano
authors.initials: E
authors.lastname: Biasini
authors.forename: Rossella
authors.initials: R
authors.lastname: Tonelli
authors.forename: Ivano
authors.initials: I
authors.lastname: Eberini
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Gianazza
authors.forename: Wei Wei
authors.initials: WW
authors.lastname: Dai
authors.forename: Maddalena
authors.initials: M
authors.lastname: Fratelli
authors.forename: Mario
authors.initials: M
authors.lastname: Salmona
authors.forename: Barbara
authors.initials: B
authors.lastname: Sherry
authors.forename: Valentina
authors.initials: V
authors.lastname: Bonetto
mesh_terms: D002942:Circular Dichroism; D019295:Computational Biology; D021984:Cyclophilin A / Q000378:metabolism*; D003545:Cysteine / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D010084:Oxidation-Reduction; D040901:Proteomics; D011994:Recombinant Proteins / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013601:T-Lymphocytes / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D021984:Cyclophilin A; D005978:Glutathione; D003545:Cysteine