GO:0035730 S-nitrosoglutathione binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0035730 (S-nitrosoglutathione binding) is a molecular_function term describing the binding of a protein to S-nitrosoglutathione (GSNO), a natural nitric oxide donor and nitrosothiol involved in S-nitrosylation and NO storage/transport.
• GSNO binding is central to protein S-nitrosylation, a reversible post-translational modification that regulates enzyme activity, receptor signaling, and transcription factor function.
• Key GSNO-binding proteins include GSNOR (ADH5), photosynthetic GAPDH, C/EBPβ, the α1-adrenergic receptor, and p65, each mediating distinct physiological outcomes.
• GSNO binding and downstream S-nitrosylation influence diverse disease processes, including diabetic vascular complications, adipogenesis, osteoclastogenesis, and host defense against pathogens.
• Structural and biochemical studies have revealed allosteric GSNO binding sites in GSNOR and defined the conformational changes that accompany GSNO binding and reactivity.
• CRISPR-based knockout, point-mutation, knock-in, and overexpression models enable causal interrogation of GSNO-binding proteins in disease and cellular signaling.
Description
S-nitrosoglutathione (GSNO) is a low-molecular-weight nitrosothiol that serves as a natural nitric oxide (NO) donor and participates in the storage and transport of NO in biological systems. The Gene Ontology term GO:0035730, S-nitrosoglutathione binding, defines the molecular function of selectively interacting with GSNO. This binding event is a prerequisite for many GSNO-dependent processes, most notably protein S-nitrosylation, a reversible post-translational modification that transfers the NO moiety from GSNO to cysteine thiols of target proteins. Because S-nitrosylation can alter enzyme catalysis, receptor ligand binding, and transcription factor activity, GSNO binding proteins act as key nodes in NO signaling. Researchers study GO:0035730 to understand how cells decode NO signals with specificity. For example, structural snapshots of photosynthetic GAPDH in complex with GSNO have revealed the conformational changes that accompany GSNO binding and subsequent S-nitrosylation. In mammals, GSNO binding to S-nitrosoglutathione reductase (GSNOR/ADH5) occurs at an allosteric site and regulates enzyme activity and intracellular GSNO homeostasis. GSNO also binds to and modifies proteins such as CCAAT/enhancer-binding protein β (C/EBPβ), the α1-adrenergic receptor, and p65, thereby influencing adipogenesis, vasoconstriction, and osteoclastogenesis, respectively. This article integrates the QuickGO definition of GO:0035730 with verified PubMed literature to provide a research-grade overview of GSNO binding mechanisms, the genes and proteins involved, disease relevance, and experimental strategies including CRISPR-based models. It is intended for scientists seeking a concise, citable resource on S-nitrosoglutathione binding and its role in health and disease.
S-nitrosoglutathione binding At A Glance
| GO ID | GO:0035730 |
|---|---|
| GO term | S-nitrosoglutathione binding |
| Ontology | molecular_function |
| Synonym | GSNO binding |
| Major function | Binding to S-nitrosoglutathione (GSNO), a natural nitric oxide donor involved in S-nitrosylation and NO storage/transport |
| Representative binders | GSNOR (ADH5), photosynthetic GAPDH, C/EBPβ, α1-adrenergic receptor, p65 |
| Biological context | Protein S-nitrosylation, NO signaling, redox regulation, host defense, metabolic regulation |
| Disease relevance | Diabetic vascular complications, adipogenesis, osteoclastogenesis, pathogen defense |
| Research methods | Structural biology, site-directed mutagenesis, CRISPR KO/point mutation/knock-in, S-nitrosylation proteomics |
What Is GO:0035730?
GO:0035730 (S-nitrosoglutathione binding) is a molecular function term defined as the binding to S-nitrosoglutathione, a nitrosothiol considered to be a natural nitric oxide (NO) donor involved in S-nitrosylation, and in the storage and transport of nitric oxide in biological systems. In practical terms, it describes any protein or biomolecule that non-covalently or covalently interacts with GSNO to mediate NO transfer, storage, or signaling. The synonym GSNO binding is commonly used in the literature.
Why Is S-nitrosoglutathione binding Important in Cell Biology?
GO:0035730 is important because GSNO binding is the first step in a major NO signaling pathway that controls protein function through S-nitrosylation. Dysregulation of GSNO binding and downstream S-nitrosylation has been linked to diabetic vascular complications, metabolic disorders, bone remodeling, and impaired host defense against pathogens. Understanding which proteins bind GSNO, where they bind it, and how binding alters their activity provides mechanistic insight into NO biology and identifies potential therapeutic targets, such as GSNOR, for pharmacological intervention.
• GSNO binding enables targeted protein S-nitrosylation, a reversible modification analogous to phosphorylation in regulatory scope.
• GSNOR (ADH5) binds GSNO at an allosteric site, and this interaction controls intracellular GSNO levels and NO homeostasis.
• GSNO binding to C/EBPβ inhibits adipogenesis in 3T3-L1 preadipocytes, linking GSNO binding to metabolic regulation.
• GSNO binding to the α1-adrenergic receptor inhibits receptor-mediated vasoconstriction and ligand binding in pulmonary artery.
• GSNO binding and GSNOR-dependent p65 denitrosation promote osteoclastogenesis by facilitating p65 recruitment to the NFATc1 promoter.
• ADH5-mediated S-nitrosothiol homeostasis facilitates STING-dependent host defense against pathogens.
• GSNOR is a therapeutic target for diabetic vascular complications in rodent models.
• Structural studies of GSNO binding to photosynthetic GAPDH reveal conserved mechanisms of S-nitrosylation.
• GSNO binding proteins are candidate biomarkers and drug targets in redox medicine.
• CRISPR models of GSNO-binding genes enable causal testing of their roles in disease.
Molecular Mechanism of S-nitrosoglutathione binding
GSNO recognition and initial binding
In simple terms: Proteins recognize GSNO and hold it in a pocket so that the NO group can be transferred to a target cysteine.
The first step in GSNO binding is molecular recognition of the nitrosothiol by a protein binding site. Structural snapshots of photosynthetic GAPDH in complex with GSNO have captured the conformational changes that occur upon GSNO binding, revealing how the protein positions GSNO for subsequent S-nitrosylation of a catalytic cysteine. In GSNOR (ADH5), an allosteric GSNO binding site has been identified, indicating that GSNO can bind at sites distinct from the catalytic center to modulate enzyme activity. These studies establish that GSNO binding is a specific, structurally defined event rather than nonspecific association.
S-nitrosylation of target cysteines
In simple terms: Once bound, GSNO donates its NO group to a cysteine on the target protein, changing that protein's activity.
GSNO binding is coupled to transfer of the nitroso group to a reactive cysteine thiol, forming an S-nitrosothiol on the target protein. This S-nitrosylation can alter enzyme catalysis, protein-protein interactions, and DNA binding. For example, GSNO binding leads to S-nitrosation of C/EBPβ, which inhibits adipogenesis in 3T3-L1 preadipocytes. Similarly, GSNO binding to the α1-adrenergic receptor inhibits receptor-mediated vasoconstriction and ligand binding in pulmonary artery. In osteoclasts, GSNOR-dependent p65 denitrosation, the reverse of S-nitrosylation, promotes osteoclastogenesis by facilitating p65 recruitment to the NFATc1 promoter.
Allosteric regulation of GSNOR by GSNO
In simple terms: GSNO can bind to a regulatory site on GSNOR, changing how the enzyme works.
Evidence for an allosteric S-nitrosoglutathione binding site in GSNOR (ADH5) has been reported, showing that GSNO binding outside the active site can modulate enzyme activity. This allosteric mechanism provides a feedback loop in which GSNO levels influence GSNOR function, thereby contributing to S-nitrosothiol homeostasis. ADH5-mediated maintenance of S-nitrosothiol homeostasis is required for STING-dependent host defense against pathogens, linking GSNO binding to innate immunity.
Cofactors and redox environment
In simple terms: GSNO binding and NO transfer depend on the redox state of the cell and on cofactors such as NADH.
GSNOR is an NADH-dependent enzyme, and its activity in consuming GSNO is coupled to NADH oxidation. The redox environment, including glutathione levels and the presence of other nitrosothiols, influences whether GSNO binding leads to S-nitrosylation or denitrosylation. In diabetic vascular complications, GSNOR activity and GSNO levels are dysregulated, and GSNOR has been proposed as a therapeutic target in rodent models. Thus, cofactors and redox balance are integral to GSNO binding function.
Structural determinants of GSNO binding
In simple terms: The shape and chemical properties of the binding pocket determine which proteins can bind GSNO.
Structural studies of photosynthetic GAPDH have provided snapshots of GSNO binding and reactivity, revealing the residues and conformational states that stabilize GSNO and promote S-nitrosylation. In GSNOR, the allosteric GSNO binding site is distinct from the catalytic site, suggesting that GSNO can act as both a substrate and a regulatory ligand. These structural insights are guiding the design of mutants and chemical probes to dissect GSNO binding specificity.
Key Genes Involved in GO:0035730 S-nitrosoglutathione binding
The following genes and proteins have been experimentally linked to S-nitrosoglutathione binding or GSNO-dependent S-nitrosylation in the verified literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| ADH5 (GSNOR) | NADH-dependent GSNO reductase; allosteric GSNO binding site | Regulates GSNO homeostasis; target for diabetic vascular complications |
| GAPDH (photosynthetic) | GSNO binding and S-nitrosylation of catalytic cysteine | Structural model for GSNO binding and reactivity |
| CEBPB (C/EBPβ) | S-nitrosation target of GSNO; inhibits adipogenesis | Metabolic regulation in 3T3-L1 preadipocytes |
| ADRA1 (α1-adrenergic receptor) | GSNO binding inhibits receptor-mediated vasoconstriction | Pulmonary artery signaling |
| RELA (p65) | GSNOR-dependent denitrosation; promotes osteoclastogenesis | Bone remodeling and NFATc1 promoter recruitment |
| STING (TMEM173) | ADH5-mediated S-nitrosothiol homeostasis facilitates STING-dependent host defense | Innate immunity against pathogens |
| NFATC1 | Downstream target of p65 in osteoclastogenesis | Bone biology |
| GSNOR (ADH5) rodent models | GSNOR inhibition or knockout | Diabetic vascular complications |
| GAPDH (mammalian) | S-nitrosylation target; GSNO binding | Redox regulation |
| C/EBPβ (human) | Transcription factor modified by GSNO | Adipogenesis and metabolism |
| α1-adrenergic receptor (human) | G-protein coupled receptor modified by GSNO | Vascular tone |
| p65 (human) | NF-κB subunit regulated by GSNO/GSNOR | Inflammation and bone |
| ADH5 (human) | GSNO reductase | Host defense and NO homeostasis |
| GSNO (metabolite) | Nitric oxide donor and nitrosothiol | Central to GO:0035730 |
| NADH | Cofactor for GSNOR | Redox metabolism |
| Glutathione (GSH) | Redox buffer and GSNO precursor | S-nitrosothiol homeostasis |
| Nitric oxide (NO) | Signaling molecule stored/transported as GSNO | Vascular and immune signaling |
How Is S-nitrosoglutathione binding Regulated?
GSNO binding and downstream S-nitrosylation are regulated at multiple levels. GSNOR (ADH5) activity controls intracellular GSNO levels through NADH-dependent reduction, and allosteric GSNO binding to GSNOR modulates this activity. The redox environment, including glutathione availability, influences GSNO stability and the efficiency of S-nitrosylation. In disease states such as diabetic vascular complications, GSNOR expression and activity are altered, leading to changes in GSNO bioavailability. Additionally, S-nitrosylation is reversible, and denitrosation reactions, such as GSNOR-dependent p65 denitrosation, provide dynamic regulation of protein function.
S-nitrosoglutathione binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| ADH5 (GSNOR) | Diabetic vascular complications | Rodent knockout or pharmacological inhibition |
| CEBPB | Adipogenesis and metabolic regulation | 3T3-L1 preadipocyte knockout or point mutation |
| RELA (p65) | Osteoclastogenesis and bone remodeling | Osteoclast precursor knockout or knock-in |
| STING (TMEM173) | Host defense against pathogens | Macrophage knockout or overexpression |
| ADRA1 | Pulmonary vasoconstriction | Pulmonary artery smooth muscle cell models |
Diabetic vascular complications
GSNOR has been identified as a therapeutic target for diabetic vascular complications in rodent models, where modulation of GSNO levels and GSNO binding affects vascular function. Dysregulated GSNO metabolism contributes to endothelial dysfunction and vascular remodeling in diabetes.
Metabolic disorders and adipogenesis
GSNO inhibits adipogenesis in 3T3-L1 preadipocytes by S-nitrosation of C/EBPβ, linking GSNO binding to metabolic regulation. This suggests that GSNO-binding proteins may be relevant to obesity and metabolic syndrome research.
Bone remodeling and osteoclastogenesis
GSNOR-dependent p65 denitrosation promotes osteoclastogenesis by facilitating recruitment of p65 to the NFATc1 promoter, implicating GSNO binding and S-nitrosothiol homeostasis in bone biology.
Host defense and immunity
ADH5-mediated S-nitrosothiol homeostasis facilitates STING-dependent host defense against pathogens, connecting GSNO binding to innate immune signaling.
From S-nitrosoglutathione binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of GSNOR alter GSNO levels and vascular function? | ADH5 knockout rodent or cell line |
| Does GSNO binding to C/EBPβ require a specific cysteine? | CEBPB point-mutation knock-in in 3T3-L1 cells |
| Does allosteric GSNO binding regulate GSNOR activity? | GSNOR point-mutation knock-in or overexpression |
| Does p65 denitrosation affect osteoclastogenesis? | RELA knockout or knock-in in osteoclast precursors |
| Does ADH5-mediated S-nitrosothiol homeostasis affect STING signaling? | ADH5 knockout macrophages with STING reporter |
| Can GSNO binding be mapped proteome-wide? | Tagged GSNO probes with mass spectrometry |
How to Study the S-nitrosoglutathione binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| X-ray crystallography | Three-dimensional structure of GSNO-protein complexes | Mapping GSNO binding sites |
| Mass spectrometry proteomics | Identification of S-nitrosylated proteins | Global GSNO target discovery |
| Isothermal titration calorimetry | Binding affinity (Kd) for GSNO | Characterizing GSNOR allosteric site |
| Site-directed mutagenesis | Role of specific residues in GSNO binding | Validating binding pockets |
| CRISPR knockout | Loss-of-function phenotype | Testing GSNO-binding gene function |
| CRISPR point mutation | Effect of specific amino acid changes | Dissecting binding vs catalysis |
| CRISPR knock-in | Tagged or mutant protein expression | Imaging and interaction studies |
| Overexpression | Gain-of-function effects | Testing sufficiency of GSNO binding |
Structural biology of GSNO binding
X-ray crystallography and cryo-EM can capture GSNO-bound states of proteins such as photosynthetic GAPDH, revealing the conformational changes that accompany GSNO binding and S-nitrosylation. These methods define the binding pocket and guide mutagenesis.
S-nitrosylation proteomics
Biotin-switch or resin-assisted capture coupled to mass spectrometry can identify proteins that bind GSNO or undergo S-nitrosylation, providing a systems-level view of GO:0035730-related proteins.
Biochemical binding assays
Isothermal titration calorimetry, surface plasmon resonance, and fluorescence polarization can measure GSNO binding affinity and kinetics for purified proteins such as GSNOR and C/EBPβ.
CRISPR-based functional assays
Knockout, point-mutation, and knock-in cell models enable causal testing of GSNO-binding proteins in processes such as adipogenesis, osteoclastogenesis, and host defense.
How CRISPR Can Be Used to Study GO:0035730 S-nitrosoglutathione binding
Knockout
CRISPR knockout of GSNO-binding genes such as ADH5, CEBPB, or RELA enables loss-of-function studies to determine their role in GSNO homeostasis, adipogenesis, and osteoclastogenesis. Knockout models are essential for establishing causality in disease pathways.
Point Mutation
Point-mutation knock-in of specific cysteine or binding-pocket residues can distinguish GSNO binding from catalytic activity. For example, mutating the allosteric GSNO binding site in GSNOR can test its regulatory role, and mutating the S-nitrosylation site in C/EBPβ can test its role in adipogenesis.
Knock-in
Tagged knock-in of GSNO-binding proteins (e.g., GFP or HA tags) allows visualization and immunoprecipitation of endogenous complexes, facilitating studies of GSNO binding dynamics and protein interactions.
Overexpression
Overexpression of wild-type or mutant GSNO-binding proteins can test sufficiency and dominant-negative effects. For example, overexpressing GSNOR mutants can reveal how allosteric GSNO binding regulates enzyme activity.
How EDITGENE Supports S-nitrosoglutathione binding Research
Researchers studying S-nitrosoglutathione binding-related genes often need to determine whether a candidate gene is causally involved in GSNO-dependent signaling, metabolism, or disease. EDITGENE provides CRISPR-based cell models and screening services to accelerate this discovery process.
Contact EDITGENE today to design your custom CRISPR model for S-nitrosoglutathione binding research.
Frequently Asked Questions About S-nitrosoglutathione binding
What is S-nitrosoglutathione binding?
S-nitrosoglutathione binding (GO:0035730) is the molecular function of binding to S-nitrosoglutathione (GSNO), a natural nitric oxide donor involved in S-nitrosylation and NO storage/transport.
What genes are involved in S-nitrosoglutathione binding?
Key genes include ADH5 (GSNOR), CEBPB, RELA (p65), STING, and ADRA1, as well as photosynthetic GAPDH in plants.
What is the GO ID for S-nitrosoglutathione binding?
The GO ID is GO:0035730, under the molecular_function ontology.
How does GSNO binding lead to S-nitrosylation?
GSNO binds to a protein pocket and transfers its nitroso group to a cysteine thiol, forming an S-nitrosothiol that alters protein function.
What diseases are linked to S-nitrosoglutathione binding?
Diabetic vascular complications, metabolic disorders, bone remodeling, and impaired host defense have been linked to GSNO binding and GSNOR activity.
What is the role of GSNOR in GSNO binding?
GSNOR (ADH5) binds GSNO at an allosteric site and reduces GSNO in an NADH-dependent manner, controlling S-nitrosothiol homeostasis.
Can CRISPR be used to study GSNO binding?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models enable causal studies of GSNO-binding proteins.
What methods study S-nitrosoglutathione binding?
Structural biology, mass spectrometry proteomics, biochemical binding assays, and CRISPR functional assays are commonly used.
Does GSNO binding affect adipogenesis?
Yes, GSNO inhibits adipogenesis in 3T3-L1 preadipocytes by S-nitrosation of C/EBPβ.
Is GSNO binding relevant to immunity?
Yes, ADH5-mediated S-nitrosothiol homeostasis facilitates STING-dependent host defense against pathogens.
Conclusion
GO:0035730 (S-nitrosoglutathione binding) defines a molecular function central to nitric oxide signaling through S-nitrosylation. The verified literature shows that GSNO binding regulates diverse proteins including GSNOR, C/EBPβ, the α1-adrenergic receptor, and p65, with impacts on vascular biology, metabolism, bone remodeling, and immunity. Continued research using structural, proteomic, and CRISPR-based approaches will clarify how GSNO binding specificity is achieved and how it can be targeted therapeutically.
References
- 1. Zhao S et al.. 2025. S-nitrosoglutathione reductase as a therapeutic target for diabetic vascular complications in rodent models.. Sci Transl Med 17(818):eadn9216 PMID: 41032622
- 2. Mattioli EJ et al.. 2022. Structural snapshots of nitrosoglutathione binding and reactivity underlying S-nitrosylation of photosynthetic GAPDH.. Redox Biol 54:102387 PMID: 35793584
- 3. Mussbacher M et al.. 2019. S-nitrosoglutathione inhibits adipogenesis in 3T3-L1 preadipocytes by S-nitrosation of CCAAT/enhancer-binding protein β.. Sci Rep 9(1):15403 PMID: 31659183
- 4. Fontana K et al.. 2019. Evidence for an Allosteric S-Nitrosoglutathione Binding Site in S-Nitrosoglutathione Reductase (GSNOR).. Antioxidants (Basel) 8(11) PMID: 31766125
- 5. Nozik-Grayck E et al.. 2006. S-nitrosoglutathione inhibits alpha1-adrenergic receptor-mediated vasoconstriction and ligand binding in pulmonary artery.. Am J Physiol Lung Cell Mol Physiol 290(1):L136-43 PMID: 16126786
- 6. Jia M et al.. 2024. S-nitrosothiol homeostasis maintained by ADH5 facilitates STING-dependent host defense against pathogens.. Nat Commun 15(1):1750 PMID: 38409248
- 8. Liu S et al.. 2024. S-nitrosoglutathione reductase-dependent p65 denitrosation promotes osteoclastogenesis by facilitating recruitment of p65 to NFATc1 promoter.. Bone 181:117036 PMID: 38311303
