Structural basis of mitochondrial dysfunction in response to cytochrome c phosphorylation at tyrosine 48.Moreno-Beltran, B., Guerra-Castellano, A., Diaz-Quintana, A., Del Conte, R., Garcia-Maurino, S.M., Diaz-Moreno, S., Gonzalez-Arzola, K., Santos-Ocana, C., Velazquez-Campoy, A., De la Rosa, M.A., Turano, P., Diaz-Moreno, I.
(2017) Proc Natl Acad Sci U S A 114: E3041-E3050
- PubMed: 28348229
- DOI: https://doi.org/10.1073/pnas.1618008114
- Primary Citation of Related Structures:
- PubMed Abstract:
Regulation of mitochondrial activity allows cells to adapt to changing conditions and to control oxidative stress, and its dysfunction can lead to hypoxia-dependent pathologies such as ischemia and cancer. Although cytochrome c phosphorylation-in particular, at tyrosine 48-is a key modulator of mitochondrial signaling, its action and molecular basis remain unknown. Here we mimic phosphorylation of cytochrome c by replacing tyrosine 48 with p -carboxy-methyl-l-phenylalanine ( p CMF). The NMR structure of the resulting mutant reveals significant conformational shifts and enhanced dynamics around p CMF that could explain changes observed in its functionality: The phosphomimetic mutation impairs cytochrome c diffusion between respiratory complexes, enhances hemeprotein peroxidase and reactive oxygen species scavenging activities, and hinders caspase-dependent apoptosis. Our findings provide a framework to further investigate the modulation of mitochondrial activity by phosphorylated cytochrome c and to develop novel therapeutic approaches based on its prosurvival effects.
Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Unit BIFI-Instituto Química-Física Rocasolano (CSIC), Universidad de Zaragoza, 50018 Zaragoza, Spain.