Aberrant Protein S-Nitrosylation in Neurodegenerative Diseases.

Del E. Web Center for Neuroscience, Aging, and Stem Cell Research, Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA. Electronic address: .
Neuron (Impact Factor: 15.98). 05/2013; 78(4):596-614. DOI: 10.1016/j.neuron.2013.05.005
Source: PubMed

ABSTRACT S-Nitrosylation is a redox-mediated posttranslational modification that regulates protein function via covalent reaction of nitric oxide (NO)-related species with a cysteine thiol group on the target protein. Under physiological conditions, S-nitrosylation can be an important modulator of signal transduction pathways, akin to phosphorylation. However, with aging or environmental toxins that generate excessive NO, aberrant S-nitrosylation reactions can occur and affect protein misfolding, mitochondrial fragmentation, synaptic function, apoptosis or autophagy. Here, we discuss how aberrantly S-nitrosylated proteins (SNO-proteins) play a crucial role in the pathogenesis of neurodegenerative diseases, including Alzheimer's and Parkinson's diseases. Insight into the pathophysiological role of aberrant S-nitrosylation pathways will enhance our understanding of molecular mechanisms leading to neurodegenerative diseases and point to potential therapeutic interventions.

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Jun 2, 2014