Cardioprotection by S-nitrosation of a cysteine switch on mitochondrial complex I

Nitric oxide donors protect from myocardial ischemia-reperfusion injury, but the underlying mechanisms have been unclear. Edward T Chouchani et al. uncover the molecular target of such donors, a cysteine residue in a subunit of complex I of the mitochondrial respiratory chain, and suggest that this cysteine residue has a general role in regulating complex I activity and modulating ischemia-reperfusion injury.