Article

Cysteine 203 of Cyclophilin D Is Critical for Cyclophilin D Activation of the Mitochondrial Permeability Transition Pore

Systems Biology Center, NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA.
Journal of Biological Chemistry (Impact Factor: 4.57). 09/2011; 286(46):40184-92. DOI: 10.1074/jbc.M111.243469
Source: PubMed

ABSTRACT

The mitochondrial permeability transition pore (mPTP) opening plays a critical role in mediating cell death during ischemia/reperfusion (I/R) injury. Our previous studies have shown that cysteine 203 of cyclophilin D (CypD), a critical mPTP mediator, undergoes protein S-nitrosylation (SNO). To investigate the role of cysteine 203 in mPTP activation, we mutated cysteine 203 of CypD to a serine residue (C203S) and determined its effect on mPTP opening. Treatment of WT mouse embryonic fibroblasts (MEFs) with H(2)O(2) resulted in an 50% loss of the mitochondrial calcein fluorescence, suggesting substantial activation of the mPTP. Consistent with the reported role of CypD in mPTP activation, CypD null (CypD(-/-)) MEFs exhibited significantly less mPTP opening. Addition of a nitric oxide donor, GSNO, to WT but not CypD(-/-) MEFs prior to H(2)O(2) attenuated mPTP opening. To test whether Cys-203 is required for this protection, we infected CypD(-/-) MEFs with a C203S-CypD vector. Surprisingly, C203S-CypD reconstituted MEFs were resistant to mPTP opening in the presence or absence of GSNO, suggesting a crucial role for Cys-203 in mPTP activation. To determine whether mutation of C203S-CypD would alter mPTP in vivo, we injected a recombinant adenovirus encoding C203S-CypD or WT CypD into CypD(-/-) mice via tail vein. Mitochondria isolated from livers of CypD(-/-) mice or mice expressing C203S-CypD were resistant to Ca(2+)-induced swelling as compared with WT CypD-reconstituted mice. Our results indicate that the Cys-203 residue of CypD is necessary for redox stress-induced activation of mPTP.

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    • "Adenine nucleotide translocator (ANT), which is required for ATP/ADP exchange, is also basally S-glutathionylated[53]. Decreased PGlu of ANT is associated with mitochondrial permeability transition pore (MPTP) opening and apoptosis in neurological tissue[53]. Similarly cyclophilin D is S-glutathionylated which prevents induction of mi- toptosis[54]. To complicate matters further GSH is also able to S-glutathionylate target proteins. "
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    • "Previous studies have demonstrated that post-translational modifications of CyPD by phosphorylation and nitrosylation regulate PTP opening [12] [13] [14]. Other studies showed that CyPD can also be acetylated on lysine 166 [15] [16]. "
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    Full-text · Article · Apr 2015 · Journal of Molecular and Cellular Cardiology
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    • "Indeed, ablation of CyP-D renders the PTP insensitive to CsA and doubles the threshold Ca 2+ load required to open the PTP in the presence of phosphate anion (Pi) [41] [42] [43] [44]. Notably, CyP-D can undergo several post-translation modifications, including phosphorylation [45], acetylation [46], and nitrosylation [47] [48]; CyP-D can also interact with a variety of proteins, such as Bcl-2 [49], the Ser/Thr kinase GSK-3 [45], the chaperones Hsp90, TRAP1 [50] and Hsp60 [51], and the FOF1 ATP synthase [52]. These dynamic changes of CyP-D affect the PTP, providing a remarkable level of flexibility in its modes of regulation. "
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