Selective prion protein binding to synaptic components is modulated by oxidative and nitrosative changes induced by copper(II) and peroxynitrite in cholinergic synaptosomes, unveiling a role for calcineurin B and thioredoxin.
Choline acetyltransferase (ChAT) and choline transport are decreased after nitrosative stress. ChAT activity is altered in scrapie-infected neurons, where oxidative stress develops. Cellular prion protein (PrPc) may play a neuroprotective function in participating in the redox control of neuronal environment and regulation of copper metabolism, a role impaired when PrPc is transformed into PrPSc in prion pathologies. The complex cross-talk between PrPc and cholinergic neurons was analyzed in vitro using peroxynitrite and Cu2+ treatments on nerve endings isolated from Torpedo marmorata, a model of the motoneuron pre-synaptic element. Specific interactions between solubilized synaptic components and recombinant ovine prion protein (PrPrec) could be demonstrated by Biacore technology. Peroxynitrite abolished this interaction in a concentration-dependent way and induced significant alterations of neuronal targets. Interaction was restored by prior addition of peroxynitrite trapping agents. Cu2+ (in the form of CuSO4) treatment of synaptosomes triggered a milder oxidative effect leading to a bell-shaped increase of PrPrec binding to synaptosomal components, counteracted by the natural thiol agents, glutathione and thioredoxin. Copper(II)-induced modifications of thiols in several neuronal proteins. A positive correlation was observed between PrPrec binding and immunoreactive changes for calcineurin B and its partners, suggesting a synergy between calcineurin complex and PrP for copper regulation.
Morot-Gaudry-Talarmain
Y
Y
Laboratoire de Neurobiologie Cellulaire et Moléculaire, CNRS, Gif-sur-Yvette, France. morot@nbcm.cnrs-gif.fr
Rezaei
H
H
Guermonprez
L
L
Treguer
E
E
Grosclaude
J
J
D048948:14-3-3 Proteins; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D019703:Calcineurin / Q000378:metabolism*; D002232:Carbocyanines / Q000378:metabolism; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D019327:Copper Sulfate / Q000494:pharmacology*; D021984:Cyclophilin A / Q000378:metabolism; D003545:Cysteine / Q000031:analogs & derivatives* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D006801:Humans; D066298:In Vitro Techniques; D008562:Membrane Glycoproteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008623:Mercaptoethanol / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000187:drug effects; D015538:Nitrosation / Q000187:drug effects; D010084:Oxidation-Reduction / Q000187:drug effects; D030421:Peroxynitrous Acid / Q000494:pharmacology*; D011328:Prions / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding; D019289:Pyruvic Acid / Q000494:pharmacology; D050765:Qa-SNARE Proteins; D050683:R-SNARE Proteins; D011994:Recombinant Proteins / Q000378:metabolism; D026403:S-Nitrosothiols / Q000378:metabolism; D012756:Sheep; D016704:Synapsins / Q000378:metabolism; D013572:Synaptic Vesicles / Q000187:drug effects; D013574:Synaptosomes / Q000187:drug effects* / Q000378:metabolism; D022021:Tacrolimus Binding Proteins / Q000378:metabolism; D013879:Thioredoxins / Q000378:metabolism*; D013997:Time Factors; D014101:Torpedo; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D048948:14-3-3 Proteins; C101089:CM-DiI; D002232:Carbocyanines; D000939:Epitopes; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011328:Prions; D050765:Qa-SNARE Proteins; D050683:R-SNARE Proteins; D011994:Recombinant Proteins; D026403:S-Nitrosothiols; D016704:Synapsins; D030421:Peroxynitrous Acid; C074856:FKBP3 protein, human; C076414:SV2A protein, human; C002744:3-nitrotyrosine; D014443:Tyrosine; D013879:Thioredoxins; D008623:Mercaptoethanol; D019289:Pyruvic Acid; C021315:S-nitrosocysteine; D014446:Tyrosine 3-Monooxygenase; D002795:Choline O-Acetyltransferase; D019703:Calcineurin; D021984:Cyclophilin A; D022021:Tacrolimus Binding Proteins; C403485:tacrolimus binding protein 4; D003545:Cysteine; D019327:Copper Sulfate