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Published on: June 21, 2021
Nitrosothiol reactivity profiling identifies S-nitrosylated proteins with unexpected stability.
Jeremy S Paige1, Guoqiang Xu, Branka Stancevic
1Department of Pharmacology, Weill Medical College, Cornell University, New York, NY 10065, USA.
Chemistry & Biology
|December 23, 2008
Summary
Most protein nitrosothiols degrade quickly. However, a subset forms stable nitrosothiols, suggesting a protective protein structure, which may mediate nitric oxide's lasting cellular effects.
Area of Science:
- Biochemistry
- Cell Biology
- Proteomics
Background:
- Nitric oxide (NO) regulates protein function through S-nitrosylation of cysteine residues, forming nitrosothiols.
- Most protein nitrosothiols are unstable and rapidly degraded by cellular reducing agents.
Purpose of the Study:
- To identify stable S-nitrosylated proteins that resist degradation.
- To investigate the mechanism behind stable S-nitrosylation and its cellular implications.
Main Methods:
- Development of a novel proteomic method for profiling S-nitrosylation.
- Analysis of the stability of over 100 S-nitrosylated proteins in cellular contexts.
Main Results:
- Identification of 10 stable S-nitrosylated proteins that persist after inhibition of NO synthesis.
- Evidence suggests stable S-nitrosylation arises from protein conformational changes shielding the nitrosothiol group.
Conclusions:
- A subset of nitric oxide targets forms stable nitrosothiols within cells.
- These stable nitrosothiols likely mediate the persistent cellular effects of nitric oxide.
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