Protein denitrosylation: enzymatic mechanisms and cellular functions

Area of Science:

• Biochemistry and Molecular Biology
• Cellular Signaling
• Redox Biology

Background:

• S-Nitrosylation, a nitric oxide modification of cysteine residues, is a key signaling mechanism.
• Aberrant S-nitrosylation is implicated in numerous human diseases.
• Protein denitrosylation, the reversal of S-nitrosylation, is increasingly recognized for its regulatory roles.

Approach:

• Focus on the discovery and physiological relevance of denitrosylases.
• Highlight the S-nitrosoglutathione reductase and thioredoxin systems as key enzymatic players.
• Examine the broad impact of these systems on cellular signaling and stress protection.

Key Points:

• Denitrosylases catalyze the removal of nitric oxide from S-nitrosylated cysteine residues.
• The S-nitrosoglutathione reductase and thioredoxin systems are evolutionarily conserved and physiologically important denitrosylases.
• These enzyme systems regulate diverse cellular processes, including receptor signaling and innate immunity.

Conclusions:

• Protein denitrosylation is a critical regulatory process in cellular signaling and homeostasis.
• The S-nitrosoglutathione reductase and thioredoxin systems play fundamental roles in managing nitrosative stress and modulating biological responses.
• Understanding denitrosylation pathways offers therapeutic potential for diseases linked to dysregulated S-nitrosylation.