Calcineurin Undergoes a Conformational Switch Evoked via Peptidyl-Prolyl Isomerization.
Guasch, A., Aranguren-Ibanez, A., Perez-Luque, R., Aparicio, D., Martinez-Hyer, S., Mulero, M.C., Serrano-Candelas, E., Perez-Riba, M., Fita, I.(2015) PLoS One 10: e0134569-e0134569
- PubMed: 26248042
- DOI: https://doi.org/10.1371/journal.pone.0134569
- Primary Citation of Related Structures:
5C1V - PubMed Abstract:
A limited repertoire of PPP family of serine/threonine phosphatases with a highly conserved catalytic domain acts on thousands of protein targets to orchestrate myriad central biological roles. A major structural reorganization of human calcineurin, a ubiquitous Ser/Thr PPP regulated by calcium and calmodulin and targeted by immunosuppressant drugs cyclosporin A and FK506, is unveiled here. The new conformation involves trans- to cis-isomerization of proline in the SAPNY sequence, highly conserved across PPPs, and remodels the main regulatory site where NFATc transcription factors bind. Transitions between cis- and trans-conformations may involve peptidyl prolyl isomerases such as cyclophilin A and FKBP12, which are known to physically interact with and modulate calcineurin even in the absence of immunosuppressant drugs. Alternative conformations in PPPs provide a new perspective on interactions with substrates and other protein partners and may foster development of more specific inhibitors as drug candidates.
Organizational Affiliation:
Institut de Biologia Molecular de Barcelona (IBMB-CSIC), Parc Científic, Baldiri Reixac 10, 08028, Barcelona, Spain.