Specific nitration of tyrosines 46 and 48 makes cytochrome c assemble a non-functional apoptosome
Por:
J. GARCIA-HEREDIA, I. DIAZ-MORENO, A. DIAZ-QUINTANA, M. ORZAEZ, J. NAVARRO, M. HERVAS and M. DE LA ROSA
Publicada:
20 ene 2012
Resumen:
Under nitroxidative stress, a minor fraction of cytochrome c can be modified by tyrosine nitration. Here we analyze the specific effect of nitration of tyrosines 46 and 48 on the dual role of cytochrome c in cell survival and cell death. Our findings reveal that nitration of these two solvent-exposed residues has a negligible effect on the rate of electron transfer from cytochrome c to cytochrome c oxidase, but impairs the ability of the heme protein to activate caspase-9 by assembling a non-functional apoptosome. It seems that cytochrome c nitration under cellular stress counteracts apoptosis in light of the small amount of modified protein. We conclude that other changes such as increased peroxidase activity prevail and allow the execution of apoptosis. (C) 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Filiaciones:
J. GARCIA-HEREDIA:
Univ Seville, CSIC, Inst Bioquim Vegetal & Fotosintesis, Seville 41092, Spain
I. DIAZ-MORENO:
Univ Seville, CSIC, Inst Bioquim Vegetal & Fotosintesis, Seville 41092, Spain
A. DIAZ-QUINTANA:
Univ Seville, CSIC, Inst Bioquim Vegetal & Fotosintesis, Seville 41092, Spain
:
Ctr Invest Principe Felipe, Valencia 46012, Spain
J. NAVARRO:
Univ Seville, CSIC, Inst Bioquim Vegetal & Fotosintesis, Seville 41092, Spain
M. HERVAS:
Univ Seville, CSIC, Inst Bioquim Vegetal & Fotosintesis, Seville 41092, Spain
M. DE LA ROSA:
Univ Seville, CSIC, Inst Bioquim Vegetal & Fotosintesis, Seville 41092, Spain
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