GO:0061507 2',3'-cyclic GMP-AMP binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0061507 defines the molecular function of binding to 2',3'-cyclic GMP-AMP (2',3'-cGAMP), a cyclic purine dinucleotide second messenger.
• 2',3'-cGAMP is produced by cGAS upon cytosolic DNA sensing and activates STING to trigger innate immune signaling.
• STING is the principal high-affinity receptor for 2',3'-cGAMP, and cryo-EM structures reveal the binding mechanism.
• 2',3'-cGAMP binding is central to host defense, autoimmunity, cancer immunity, and cardiovascular/metabolic disease.
• Dysregulated 2',3'-cGAMP binding contributes to systemic and organ-specific diseases, making it a therapeutic target.
• CRISPR knockout, point-mutation, knock-in, and overexpression models enable functional dissection of 2',3'-cGAMP binding proteins.
Description
2',3'-cyclic GMP-AMP binding (GO:0061507) is a molecular function that describes the selective interaction of a protein with 2',3'-cyclic GMP-AMP (2',3'-cGAMP), a cyclic purine dinucleotide second messenger. This dinucleotide is synthesized by cyclic GMP-AMP synthase (cGAS) in response to cytosolic DNA and acts as a key ligand for stimulator of interferon genes (STING), thereby initiating innate immune signaling. The binding event is therefore a critical node in the cGAS-STING pathway, which couples DNA sensing to interferon production and inflammatory gene expression. Researchers study GO:0061507 to understand how cells detect foreign or misplaced DNA, how immune responses are amplified or restrained, and how dysregulation of this binding contributes to disease. Because 2',3'-cGAMP can also act non-cell-autonomously, its binding proteins influence intercellular communication within the tumor microenvironment and beyond. The availability of structural, biochemical, and genetic tools has made 2',3'-cGAMP binding a tractable target for drug discovery and for CRISPR-based functional genomics.
2',3'-cyclic GMP-AMP binding At A Glance
| GO ID | GO:0061507 |
|---|---|
| GO term | 2',3'-cyclic GMP-AMP binding |
| Ontology | molecular_function |
| Synonym | 2',3' cGAMP binding; 2',3'-cGAMP binding; 2',3' cyclic GAMP binding; 2',3'-cyclic GAMP binding; 2',5-3',5'-cyclic GMP-AMP binding; c[G(2',5')pA(3',5')p] binding; cyclic-GMP-AMP binding |
| Major function | Binding to the second messenger 2',3'-cGAMP, enabling downstream innate immune signaling |
| Primary receptor | STING (TMEM173) is the best-characterized 2',3'-cGAMP-binding protein |
| Ligand source | Synthesized by cGAS upon cytosolic DNA sensing |
| Pathway context | cGAS-STING innate immune signaling |
| Disease relevance | Cancer, autoimmunity, cardiovascular and metabolic diseases |
What Is GO:0061507?
In simple terms, GO:0061507 is the function of a protein grabbing onto a specific small molecule called 2',3'-cGAMP. The QuickGO definition states: binding to 2',3' cyclic GMP-AMP (cGAMP) nucleotide, a cyclic purine dinucleotide that consists of AMP and GMP units cyclized via 2',5' and 3',5' linkages. This function is distinct from binding to other cyclic dinucleotides such as 3',3'-cGAMP or bacterial cyclic di-GMP, and it is typically mediated by a conserved ligand-binding pocket. The term is used to annotate proteins that physically interact with 2',3'-cGAMP, including STING and other cellular receptors or sensors.
Why Is 2',3'-cyclic GMP-AMP binding Important in Cell Biology?
2',3'-cyclic GMP-AMP binding is important because it is the molecular switch that converts cytosolic DNA detection into a full innate immune response. Without efficient binding of 2',3'-cGAMP to STING, cells fail to produce type I interferons and other inflammatory cytokines, compromising host defense against pathogens and tumors. Conversely, excessive or chronic activation of this binding event is linked to autoimmune and inflammatory pathologies, including systemic and organ-specific diseases. The binding function is also a direct drug target: small-molecule agonists and antagonists of 2',3'-cGAMP binding are being developed for immunotherapy and for treating inflammatory conditions. In cancer, 2',3'-cGAMP binding influences both cell-autonomous and non-autonomous roles of the cGAS-STING axis, affecting tumor progression and response to immunotherapy. Thus, understanding GO:0061507 at structural and functional levels is essential for both basic immunology and translational medicine.
• Defines the first committed step in STING activation after cGAS produces 2',3'-cGAMP.
• Controls type I interferon and inflammatory cytokine production.
• Shapes anti-tumor immunity and immunotherapy responses.
• Contributes to autoimmune and autoinflammatory disease when dysregulated.
• Implicated in cardiovascular and metabolic diseases.
• Enables non-cell-autonomous signaling between cells in the tumor microenvironment.
• Provides a structural template for small-molecule drug design.
• Serves as a functional readout in CRISPR screens for innate immune regulators.
What Happens During 2',3'-cyclic GMP-AMP binding?
Synthesis of 2',3'-cGAMP by cGAS
In simple terms: The cell makes the messenger molecule before anything can bind it.
In the presence of cytosolic double-stranded DNA, cGAS catalyzes the cyclization of ATP and GTP to produce 2',3'-cGAMP. This synthesis is the upstream event that generates the ligand for GO:0061507. The reaction occurs in the cytosol and is a prerequisite for subsequent binding to STING.
Recognition and binding by STING
In simple terms: STING grabs the messenger molecule inside the cell.
STING, an endoplasmic reticulum-resident transmembrane protein, contains a ligand-binding domain that specifically accommodates 2',3'-cGAMP. Cryo-EM structures show that binding induces a conformational change that oligomerizes STING and triggers downstream signaling. This binding event is the defining function of GO:0061507.
Conformational change and oligomerization
In simple terms: Binding flips a molecular switch that makes STING cluster together.
Upon 2',3'-cGAMP binding, STING undergoes a major conformational rearrangement that allows it to polymerize and translocate from the endoplasmic reticulum to the Golgi. This step is essential for recruiting TBK1 and IRF3, leading to interferon induction. The structural basis of this activation has been resolved by cryo-EM.
Downstream signaling and immune gene expression
In simple terms: The clustered STING sends a signal that turns on immune genes.
Activated STING recruits TBK1, which phosphorylates IRF3; phosphorylated IRF3 dimerizes and enters the nucleus to drive transcription of type I interferons and interferon-stimulated genes. This cascade is the functional consequence of 2',3'-cGAMP binding and is central to host defense.
Degradation and signal termination
In simple terms: The messenger is destroyed to stop the alarm.
2',3'-cGAMP is degraded by ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) and other enzymes, terminating STING activation. This degradation ensures that 2',3'-cGAMP binding is transient and tightly regulated, preventing chronic inflammation.
Key Genes Involved in GO:0061507 2',3'-cyclic GMP-AMP binding
The following genes encode proteins that directly or indirectly participate in 2',3'-cyclic GMP-AMP binding and its downstream signaling.
| Gene | Major Role | Research Relevance |
|---|---|---|
| STING1 (TMEM173) | Directly binds 2',3'-cGAMP and activates downstream signaling | Central receptor for GO:0061507; target for agonists/antagonists |
| CGAS (MB21D1) | Synthesizes 2',3'-cGAMP from ATP and GTP | Upstream enzyme controlling ligand availability |
| TBK1 | Kinase recruited by activated STING to phosphorylate IRF3 | Essential signaling node downstream of binding |
| IRF3 | Transcription factor activated by TBK1 to induce interferons | Readout of 2',3'-cGAMP binding activity |
| ENPP1 | Degrades 2',3'-cGAMP to terminate signaling | Regulates duration of binding and immune activation |
| NFKB1 | Transcription factor activated downstream of STING | Links binding to inflammatory gene expression |
| TREX1 | DNase that prevents cytosolic DNA accumulation | Loss causes cGAS-STING activation and autoimmunity |
| TMEM173 | Alternative symbol for STING1 | Same as STING1; used in structural studies |
| IFNB1 | Type I interferon gene induced by STING signaling | Functional marker of 2',3'-cGAMP binding |
| CXCL10 | Chemokine induced by interferon signaling | Biomarker of pathway activation |
| IL6 | Inflammatory cytokine induced downstream of STING | Readout of inflammatory arm |
| TNF | Inflammatory cytokine induced downstream of STING | Readout of inflammatory arm |
| ATG9A | Trafficking protein involved in STING transport | Modulates STING signaling from Golgi |
| STIM1 | Calcium sensor affecting STING trafficking | Organelle-specific regulation of signaling |
| OPTN | Autophagy receptor regulating STING degradation | Controls termination of signaling |
| RAB7A | GTPase involved in STING trafficking | Regulates Golgi-to-lysosome transport |
| SLC19A1 | Transporter for extracellular 2',3'-cGAMP uptake | Enables non-cell-autonomous signaling |
| LRRC8C | Channel mediating 2',3'-cGAMP transfer between cells | Intercellular communication in tumor microenvironment |
How Is 2',3'-cyclic GMP-AMP binding Regulated?
2',3'-cyclic GMP-AMP binding is regulated at multiple levels. Ligand availability is controlled by cGAS synthesis and ENPP1-mediated degradation. STING trafficking between the endoplasmic reticulum and Golgi is regulated by proteins such as ATG9A, STIM1, OPTN, and RAB7A, which influence the duration and intensity of signaling. Post-translational modifications of STING, including phosphorylation and ubiquitination, further modulate its activity. Extracellular 2',3'-cGAMP can be imported via SLC19A1 or transferred through LRRC8C channels, enabling non-cell-autonomous regulation. These layers ensure that 2',3'-cGAMP binding is transient and context-dependent.
2',3'-cyclic GMP-AMP binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| STING1 | Autoinflammatory diseases and cancer immunity | Knockout and point-mutation cell models |
| CGAS | Autoimmunity and tumor suppression | Knockout and overexpression models |
| TREX1 | Aicardi-Goutieres syndrome and systemic autoimmunity | Knockout and knock-in models |
| ENPP1 | Ectopic calcification and immune dysregulation | Knockout and overexpression models |
| SLC19A1 | Cancer immunotherapy response | Knockout and overexpression models |
Cancer
2',3'-cGAMP binding and the cGAS-STING axis play both cell-autonomous and non-autonomous roles in cancer progression. Activation of STING by 2',3'-cGAMP promotes anti-tumor immunity, but chronic activation can also support tumor growth in some contexts. Understanding the binding function is therefore critical for designing STING-targeted immunotherapies.
Autoimmune and Autoinflammatory Diseases
Defective regulation of 2',3'-cGAMP binding leads to chronic interferon production and autoimmunity. Mutations in TREX1 and other DNA-handling genes cause cytosolic DNA accumulation and sustained cGAS-STING activation, contributing to systemic and organ-specific diseases. Targeting 2',3'-cGAMP binding is a therapeutic strategy for these conditions.
Cardiovascular and Metabolic Diseases
The cGAS-STING pathway, including 2',3'-cGAMP binding, is implicated in cardiovascular and metabolic diseases such as atherosclerosis and insulin resistance. Chronic inflammation driven by this pathway contributes to disease progression, making it a potential pharmacotherapy target.
Organelle-Specific Signaling in Disease
Organelle-specific signaling of cGAS-STING, including at the Golgi and mitochondria, influences disease outcomes. Disruption of trafficking regulators such as ATG9A and RAB7A alters 2',3'-cGAMP binding-dependent responses. This spatial regulation is an emerging area in disease research.
From 2',3'-cyclic GMP-AMP binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does STING directly bind 2',3'-cGAMP? | Point-mutation knock-in of STING ligand-binding residues |
| What is the role of cGAS in ligand production? | CGAS knockout cell line |
| How does ENPP1 regulate signal duration? | ENPP1 overexpression and knockout models |
| Can 2',3'-cGAMP transfer between cells? | SLC19A1 and LRRC8C knockout models |
| What is the effect of STING trafficking on signaling? | ATG9A or RAB7A knockout models |
| How does chronic STING activation cause autoimmunity? | TREX1 knockout and STING knock-in models |
How to Study the 2',3'-cyclic GMP-AMP binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Cryo-EM | 3D structure of STING-ligand complex | Mechanistic studies of binding |
| Isothermal titration calorimetry | Binding affinity and thermodynamics | Drug candidate screening |
| ISRE luciferase reporter | Downstream interferon signaling | Functional validation of binding |
| qPCR for IFNB1/CXCL10 | Interferon and chemokine gene expression | Pathway activation readout |
| CRISPR knockout screen | Genes regulating 2',3'-cGAMP binding | Discovery of novel regulators |
| Co-immunoprecipitation | Protein-protein interactions of STING | Complex assembly studies |
| Live-cell imaging | STING trafficking and oligomerization | Spatiotemporal regulation |
| Mass spectrometry | Post-translational modifications of STING | Regulation studies |
Structural Biology
Cryo-EM and X-ray crystallography are used to determine how STING binds 2',3'-cGAMP at atomic resolution. These methods reveal the ligand-binding pocket and conformational changes that drive activation.
Biochemical Binding Assays
Isothermal titration calorimetry, surface plasmon resonance, and radioligand binding assays measure the affinity and specificity of 2',3'-cGAMP binding to STING and other proteins. These assays are essential for drug discovery.
Cell-Based Reporter Assays
Interferon-stimulated response element (ISRE) luciferase reporters and qPCR for IFNB1, CXCL10, and IL6 measure downstream signaling after 2',3'-cGAMP binding. These assays are used to screen agonists and antagonists.
CRISPR Functional Genomics
Genome-wide CRISPR knockout screens identify genes that regulate 2',3'-cGAMP binding and STING signaling. These screens link candidate genes to pathway activity and disease phenotypes.
How CRISPR Can Be Used to Study GO:0061507 2',3'-cyclic GMP-AMP binding
Knockout
CRISPR knockout of STING1, CGAS, or ENPP1 abolishes or alters 2',3'-cGAMP binding and downstream signaling, providing causal evidence for gene function. Knockout models are used to test whether a candidate gene is required for interferon induction.
Point Mutation
Point mutations in the STING ligand-binding pocket can selectively disrupt 2',3'-cGAMP binding without affecting protein stability, allowing precise structure-function analysis. Such models are valuable for dissecting binding versus signaling domains.
Knock-in
Knock-in of disease-associated STING or TREX1 variants recapitulates human autoinflammatory phenotypes in cell and animal models. These models help link specific mutations to altered 2',3'-cGAMP binding.
Overexpression
Overexpression of STING or cGAS enhances 2',3'-cGAMP binding and signaling, enabling gain-of-function studies and drug screening. Overexpression models are also used to study non-cell-autonomous effects.
How EDITGENE Supports 2',3'-cyclic GMP-AMP binding Research
Researchers studying 2',3'-cyclic GMP-AMP binding-related genes often need to determine whether a candidate gene is causally involved in ligand recognition, signaling, or disease progression. EDITGENE provides publication-ready CRISPR cell models and screening services to accelerate this work.
Contact EDITGENE today to design your custom CRISPR model for 2',3'-cyclic GMP-AMP binding research.
Frequently Asked Questions About 2',3'-cyclic GMP-AMP binding
What is 2',3'-cyclic GMP-AMP binding?
It is the molecular function defined by GO:0061507, describing the binding of a protein to the second messenger 2',3'-cGAMP.
What genes are involved in 2',3'-cyclic GMP-AMP binding?
Key genes include STING1, CGAS, ENPP1, TBK1, IRF3, and SLC19A1, among others.
Which protein is the main receptor for 2',3'-cGAMP?
STING (encoded by STING1/TMEM173) is the principal high-affinity receptor.
How is 2',3'-cGAMP produced?
cGAS synthesizes 2',3'-cGAMP from ATP and GTP upon sensing cytosolic DNA.
What diseases are linked to 2',3'-cGAMP binding?
Cancer, autoimmune diseases, cardiovascular disease, and metabolic disorders.
How can I study 2',3'-cGAMP binding in the lab?
Use biochemical binding assays, cell-based reporters, cryo-EM, and CRISPR screens.
What is the role of ENPP1 in 2',3'-cGAMP binding?
ENPP1 degrades 2',3'-cGAMP, terminating STING activation.
Can 2',3'-cGAMP move between cells?
Yes, it can be transported via SLC19A1 and LRRC8C, enabling non-cell-autonomous signaling.
What CRISPR models are available for this pathway?
Knockout, point-mutation, knock-in, and overexpression models for STING1, CGAS, ENPP1, and related genes.
Why is GO:0061507 important for drug discovery?
It is the molecular target of STING agonists and antagonists being developed for immunotherapy and inflammatory diseases.
Conclusion
GO:0061507, 2',3'-cyclic GMP-AMP binding, is a central molecular function in innate immunity that links cytosolic DNA sensing to interferon production and inflammation. Its structural basis, regulatory mechanisms, and disease associations are well documented, making it a prime target for therapeutic intervention. Continued research using CRISPR models and advanced biochemical assays will further clarify how this binding event can be modulated for cancer, autoimmune, and metabolic diseases.
References
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- 2. Su M et al.. 2022. Second messenger 2'3'-cyclic GMP-AMP (2'3'-cGAMP): Synthesis, transmission, and degradation.. Biochem Pharmacol 198:114934 PMID: 35104477
- 3. Ma XY et al.. 2024. Second messenger 2'3'-cyclic GMP-AMP (2'3'-cGAMP): the cell autonomous and non-autonomous roles in cancer progression.. Acta Pharmacol Sin 45(5):890-899 PMID: 38177693
- 4. Oduro PK et al.. 2022. The cGAS-STING signaling in cardiovascular and metabolic diseases: Future novel target option for pharmacotherapy.. Acta Pharm Sin B 12(1):50-75 PMID: 35127372
- 5. Liu S et al.. 2026. Organelle-specific signaling of cGAS-STING.. Trends Cell Biol 36(5):355-376 PMID: 40975693
- 6. Skopelja-Gardner S et al.. 2022. Role of the cGAS-STING pathway in systemic and organ-specific diseases.. Nat Rev Nephrol 18(9):558-572 PMID: 35732833
- 7. Shang G et al.. 2019. Cryo-EM structures of STING reveal its mechanism of activation by cyclic GMP-AMP.. Nature 567(7748):389-393 PMID: 30842659
- 8. Kato K et al.. 2017. Cyclic GMP-AMP as an Endogenous Second Messenger in Innate Immune Signaling by Cytosolic DNA.. Annu Rev Biochem 86:541-566 PMID: 28399655
