Function
Cyclophilin (Cyp) binds cyclosporin. They are peptidylprolyl isomerases which catalyze the isomerisation of proline. The Cyp-A/cyclosporin A complex inhibits organ rejection. Cyp-D is a component of the mitochondria permeability pore. Rotamase such as FKBP is a prokaryotic Cyp which is not inhibited by cyclosporin but by FK-506 – an immunosuppressive drug. [1] See also Isomerases.
Relevance
Cyp-A has a key role in immunosuppression and viral infection[2]. Cyp-A is the target of the immunosuppressant cyclosporin A whose binding leads to the suppression of the T-cell mediated immune response. Cyp-A is required for effective HIV-1 replication in host cells[3].
Structural highlights
. The acetylation modulates key functions of Cyp-A activity.[4]
3D Structures of Cyclophilin
Cyclophilin 3D structures