GO:0019002 GMP binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0019002 GMP binding is a molecular function defined as binding to guanosine monophosphate (GMP) [QuickGO].
• GMP binding is central to cyclic dinucleotide signaling, including c-di-GMP and cGAMP pathways that control bacterial biofilm formation, cell size, and host immunity [2,3,5,6].
• Key GMP-binding proteins include STING (stimulator of interferon genes), which binds cyclic GMP-AMP (cGAMP) to activate innate immune responses [5,6].
• Bacterial c-di-GMP-binding effectors regulate biofilm development, motility, and iron responses, making them attractive antibacterial targets [4,7,8].
• Dysregulation of GMP-binding proteins like STING is linked to autoinflammatory diseases and cancer [1,5].
• CRISPR knockout, knock-in, and point-mutation models are essential to dissect the causal roles of GMP-binding proteins in health and disease.
Description
Guanosine monophosphate (GMP) is a nucleotide that serves as a building block of RNA and as a signaling molecule when cyclized to form cyclic di-GMP (c-di-GMP) or cyclic GMP-AMP (cGAMP). The Gene Ontology term GO:0019002, GMP binding, describes the molecular function of selectively interacting with GMP [QuickGO]. This function is critical for diverse biological processes, from bacterial biofilm formation to mammalian innate immunity [2,5]. Understanding GMP binding is therefore essential for researchers studying signal transduction, host-pathogen interactions, and immune regulation. The importance of GMP binding is underscored by the many proteins that have evolved to recognize cyclic dinucleotides. For example, the mammalian adaptor protein STING binds cGAMP with high affinity to trigger interferon production. In bacteria, c-di-GMP-binding proteins such as Scr transcription factors and H-NS modulate biofilm development and gene expression [4,7]. These examples highlight the broad relevance of GMP binding across kingdoms. This article provides a comprehensive overview of GO:0019002, covering its definition, molecular mechanisms, key genes, disease associations, and research methodologies. By integrating authoritative QuickGO data with verified PubMed literature, we aim to equip researchers with a clear framework for studying GMP-binding proteins and their roles in health and disease.
GMP binding At A Glance
| GO ID | GO:0019002 |
|---|---|
| GO term | GMP binding |
| Ontology | molecular_function |
| Synonym | None |
| Definition | Binding to GMP, guanosine monophosphate. |
| Major function | Selective interaction with GMP and its cyclic derivatives, mediating signal transduction and regulatory processes. |
| Related molecules | c-di-GMP, cGAMP, GTP, GDP |
| Representative proteins | STING, Scr transcription factors, H-NS, c-di-GMP effectors |
| Disease relevance | Autoinflammatory diseases, cancer, bacterial infections |
What Is GO:0019002?
According to the Gene Ontology, GO:0019002 GMP binding is the molecular function of binding to guanosine monophosphate (GMP), a nucleotide consisting of a guanine base, a ribose sugar, and a single phosphate group [QuickGO]. This term encompasses non-covalent interactions with GMP, including its cyclic forms such as c-di-GMP and cGAMP, which are key second messengers [2,5]. GMP binding is distinct from other nucleotide-binding functions due to the specific recognition of the guanine moiety and the phosphate group.
Why Is GMP binding Important in Cell Biology?
GMP binding is a fundamental molecular function that underlies critical signaling pathways in both prokaryotes and eukaryotes. In bacteria, c-di-GMP binding controls biofilm formation, motility, and virulence, making it a prime target for anti-infective strategies [2,7,8]. In mammals, cGAMP binding by STING is central to innate immune sensing of cytosolic DNA and is implicated in autoinflammatory diseases and cancer immunotherapy [1,5,6]. Thus, understanding GMP binding at the molecular level is essential for developing therapeutics that modulate these pathways.
• GMP binding is essential for bacterial cyclic di-GMP signaling, which regulates biofilm formation and virulence [2,7].
• The cGAMP-STING interaction is a key mechanism in mammalian innate immunity against pathogens and tumors [5,6].
• Dysregulation of STING leads to autoinflammatory diseases such as STING-associated vasculopathy.
• c-di-GMP-binding proteins control cell size in cyanobacteria, linking GMP binding to cellular morphogenesis.
• In Salmonella, c-di-GMP binding to H-NS inhibits DNA binding, affecting gene expression and pathogenesis.
• Pseudomonas aeruginosa uses c-di-GMP signaling to respond to iron availability, impacting infection.
• GMP-binding proteins are potential drug targets for antibiotics and immunotherapies [2,5].
• Studying GMP binding helps elucidate mechanisms of antibiotic resistance and immune evasion [4,7].
• CRISPR-based models enable precise interrogation of GMP-binding protein functions in disease [1,5].
• GMP binding research bridges microbiology, immunology, and cancer biology, offering broad translational potential [6,8].
Molecular Mechanism of GMP binding
Substrate Recognition and Binding Pocket
In simple terms: GMP fits into a specific pocket in the protein, like a key in a lock.
GMP-binding proteins typically contain a conserved binding pocket that recognizes the guanine base through hydrogen bonding and stacking interactions. For example, STING binds cGAMP with high affinity via a pocket formed by conserved tyrosine and arginine residues [5,6]. In bacterial c-di-GMP effectors, the binding pocket often includes a RxxD motif or a PilZ domain that specifically coordinates the cyclic dinucleotide [2,7].
Conformational Changes and Activation
In simple terms: When GMP binds, the protein changes shape to turn on a signal.
Binding of GMP or its cyclic forms induces conformational changes that activate downstream signaling. STING undergoes a dramatic rearrangement upon cGAMP binding, leading to its oligomerization and recruitment of TBK1 [1,5]. Similarly, c-di-GMP binding to transcription factors like ScrC in Vibrio parahaemolyticus triggers DNA binding and biofilm gene expression.
Cofactors and Regulatory Ions
In simple terms: Some proteins need helper molecules or ions to bind GMP effectively.
Certain GMP-binding proteins require metal ions or cofactors for optimal binding. For instance, the c-di-GMP effector in cyanobacteria may utilize magnesium ions to stabilize the binding pocket. In H-NS, c-di-GMP binding is modulated by pH and ionic strength, suggesting environmental regulation.
Signal Transduction and Downstream Effects
In simple terms: After binding, the protein sends a message to other molecules.
Once GMP is bound, the protein initiates signaling cascades. STING activates TBK1, which phosphorylates IRF3 to induce interferon genes [1,5]. In bacteria, c-di-GMP binding to effectors alters second messenger levels, controlling motility, biofilm formation, and iron acquisition.
Regulation of GMP Binding
In simple terms: Cells control when and where GMP binding happens.
GMP binding is regulated by the availability of GMP and its cyclic forms, which are synthesized and degraded by specific enzymes (e.g., diguanylate cyclases and phosphodiesterases). Post-translational modifications of GMP-binding proteins, such as phosphorylation of STING, can also modulate binding affinity.
Key Genes Involved in GO:0019002 GMP binding
The following genes encode proteins that bind GMP or its cyclic derivatives, playing diverse roles in signaling and disease.
| Gene | Major Role | Research Relevance |
|---|---|---|
| STING1 | Binds cGAMP to activate innate immune signaling | Autoinflammatory diseases, cancer immunotherapy [1,5] |
| TBK1 | Phosphorylates STING and IRF3 downstream of cGAMP binding | Immune signaling, drug target |
| ScrC | c-di-GMP-binding transcription factor regulating biofilm genes | Vibrio parahaemolyticus biofilm formation |
| ScrA | Homologous c-di-GMP-binding transcription factor | Biofilm development |
| H-NS | Binds c-di-GMP, inhibiting DNA binding | Salmonella gene regulation and virulence |
| PilZ | c-di-GMP-binding domain in various bacterial proteins | Bacterial motility and biofilm |
| DgcA | Diguanylate cyclase synthesizing c-di-GMP | Cyanobacterial cell size control |
| PdeA | Phosphodiesterase degrading c-di-GMP | Regulation of c-di-GMP levels |
| cGAS | Synthesizes cGAMP from ATP and GTP | Innate immune sensing of DNA |
| STING | Adaptor protein binding cGAMP | Interferonopathies, cancer |
| RocR | c-di-GMP-binding transcription factor | Pseudomonas aeruginosa iron response |
| FimX | c-di-GMP-binding protein involved in twitching motility | Pseudomonas aeruginosa virulence |
| YfiN | Diguanylate cyclase | Biofilm regulation |
| BcsA | Cellulose synthase with c-di-GMP-binding PilZ domain | Biofilm matrix production |
| LapD | c-di-GMP-binding protein controlling adhesin secretion | Biofilm formation |
| Clp | c-di-GMP-binding protein in cyanobacteria | Cell size regulation |
| VpsT | c-di-GMP-binding transcription factor | Vibrio cholerae biofilm |
| FleQ | c-di-GMP-binding transcription factor | Flagellar motility |
How Is GMP binding Regulated?
GMP binding is regulated at multiple levels. The intracellular concentration of GMP and its cyclic forms is controlled by the opposing activities of diguanylate cyclases (DGCs) and phosphodiesterases (PDEs). In mammals, cGAMP levels are regulated by cGAS and its degradation by ENPP1. Post-translational modifications, such as phosphorylation of STING by TBK1, can enhance or inhibit its binding to cGAMP. Additionally, environmental cues like iron availability modulate c-di-GMP signaling in Pseudomonas aeruginosa.
GMP binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| STING1 | SAVI, autoinflammation | Knock-in of SAVI mutations in mice |
| cGAS | Cancer immune evasion | Knockout in tumor cell lines |
| ScrC | Vibrio biofilm formation | Knockout in Vibrio parahaemolyticus |
| H-NS | Salmonella virulence | Point mutation in Salmonella |
| RocR | Pseudomonas iron response | Knockout in P. aeruginosa |
Autoinflammatory Diseases
Gain-of-function mutations in STING1 cause STING-associated vasculopathy with onset in infancy (SAVI), a severe autoinflammatory disease characterized by constitutive interferon signaling. These mutations often enhance cGAMP binding or oligomerization, leading to chronic immune activation.
Cancer
The cGAS-STING pathway is critical for antitumor immunity. cGAMP binding to STING activates cytotoxic T cells and is a target for cancer immunotherapy [5,6]. However, tumors can evade this pathway by downregulating STING or cGAS.
Bacterial Infections
c-di-GMP-binding proteins regulate biofilm formation and virulence in pathogens like Vibrio parahaemolyticus, Salmonella, and Pseudomonas aeruginosa [4,7,8]. Targeting these proteins could disrupt biofilm-associated infections.
From GMP binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does STING cGAMP binding drive autoinflammation? | Knock-in mouse expressing STING V155M |
| Is cGAS required for antitumor immunity? | cGAS knockout mice |
| How does c-di-GMP binding affect biofilm? | ScrC knockout in Vibrio |
| Does H-NS c-di-GMP binding regulate virulence? | Point mutation in H-NS |
| What is the role of c-di-GMP in iron response? | RocR knockout in Pseudomonas |
| Can STING be targeted for cancer therapy? | Overexpression of STING in tumor models |
How to Study the GMP binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Cryo-EM | High-resolution structure of protein-GMP complexes | STING-cGAMP structure |
| ITC | Binding affinity (Kd) | cGAMP-STING interaction |
| CRISPR knockout screen | Genes affecting GMP signaling | Identify regulators of STING |
| Fluorescence microscopy | Subcellular localization | STING trafficking |
| Western blot | Protein expression and phosphorylation | TBK1 activation |
| qRT-PCR | Gene expression changes | Interferon signature |
| Biofilm assay | Biofilm formation | c-di-GMP effects |
| Motility assay | Bacterial swimming/swarming | c-di-GMP regulation |
Structural Biology
X-ray crystallography and cryo-EM have elucidated the atomic details of GMP binding. For example, cryo-EM structures of STING bound to cGAMP revealed the conformational changes required for activation. These methods are essential for understanding binding specificity and designing inhibitors.
Biochemical Binding Assays
Isothermal titration calorimetry (ITC) and surface plasmon resonance (SPR) measure binding affinity between GMP derivatives and proteins. Such assays have quantified the high-affinity interaction between cGAMP and STING.
Genetic Screens
CRISPR knockout screens can identify genes required for GMP-mediated signaling. For instance, genome-wide screens have uncovered regulators of cGAS-STING pathway.
Cellular Imaging
Fluorescence microscopy using GFP-tagged GMP-binding proteins visualizes their localization and dynamics. This approach has shown STING trafficking upon cGAMP binding.
How CRISPR Can Be Used to Study GO:0019002 GMP binding
Knockout
CRISPR knockout of GMP-binding genes (e.g., STING1, cGAS) in cell lines or mice ablates signaling, revealing their essential roles in immunity and disease [1,6].
Point Mutation
Introducing disease-associated point mutations (e.g., STING V155M) via CRISPR base editing or HDR recapitulates autoinflammatory phenotypes and tests causality.
Knock-in
Knock-in of tagged GMP-binding proteins (e.g., GFP-STING) enables live-cell imaging and proteomic analysis of binding dynamics.
Overexpression
Overexpression of GMP-binding proteins or their mutants can amplify signaling and facilitate biochemical purification for structural studies.
How EDITGENE Supports GMP binding Research
Researchers studying GMP binding-related genes often need to determine whether a candidate gene is causally involved in a specific pathway or disease. CRISPR-based models provide a robust way to test gene function by creating precise genetic alterations.
Contact EDITGENE today to design your custom CRISPR model for GMP binding research.
Frequently Asked Questions About GMP binding
What is GMP binding?
GMP binding is a molecular function defined by the Gene Ontology as binding to guanosine monophosphate (GMP), a nucleotide involved in signaling and metabolism [QuickGO].
What genes are involved in GMP binding?
Key genes include STING1, cGAS, ScrC, H-NS, and RocR, which encode proteins that bind GMP or its cyclic derivatives [1,4,6,7,8].
What is the GO ID for GMP binding?
The GO ID for GMP binding is GO:0019002.
How does GMP binding affect immunity?
GMP binding by STING to cGAMP activates interferon signaling, crucial for antiviral and antitumor immunity [5,6].
What diseases are associated with GMP binding?
Dysregulation of GMP-binding proteins is linked to autoinflammatory diseases like SAVI, cancer, and bacterial infections [1,5,7].
What are the methods to study GMP binding?
Common methods include cryo-EM, ITC, CRISPR screens, and fluorescence microscopy [5,6].
Can CRISPR be used to study GMP binding?
Yes, CRISPR knockout, knock-in, and point mutation models are widely used to dissect GMP-binding protein functions [1,6].
What is c-di-GMP?
c-di-GMP is a cyclic dinucleotide that binds to effector proteins to regulate bacterial biofilm formation and motility [2,7].
How is GMP binding regulated?
GMP binding is regulated by synthesis and degradation of cyclic dinucleotides, as well as post-translational modifications of binding proteins [1,2].
Why is GMP binding important for drug discovery?
GMP-binding proteins are targets for antibiotics and immunotherapies, as they control bacterial virulence and immune responses [2,5].
Conclusion
GMP binding (GO:0019002) is a versatile molecular function that governs critical signaling pathways in bacteria and mammals. From bacterial biofilm control to human innate immunity, GMP-binding proteins are central to health and disease. Continued research using advanced CRISPR models and structural techniques will further illuminate their mechanisms and therapeutic potential.
References
- 1. Zhang C et al.. 2019. Structural basis of STING binding with and phosphorylation by TBK1.. Nature 567(7748):394-398 PMID: 30842653
- 2. Chou SH et al.. 2016. Diversity of Cyclic Di-GMP-Binding Proteins and Mechanisms.. J Bacteriol 198(1):32-46 PMID: 26055114
- 3. Zeng X et al.. 2023. A c-di-GMP binding effector controls cell size in a cyanobacterium.. Proc Natl Acad Sci U S A 120(13):e2221874120 PMID: 36947515
- 4. Li S et al.. 2023. c-di-GMP inhibits the DNA binding activity of H-NS in Salmonella.. Nat Commun 14(1):7502 PMID: 37980414
- 5. 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
- 6. Zhang X et al.. 2013. Cyclic GMP-AMP containing mixed phosphodiester linkages is an endogenous high-affinity ligand for STING.. Mol Cell 51(2):226-35 PMID: 23747010
- 7. Kimbrough JH et al.. 2020. Homologous c-di-GMP-Binding Scr Transcription Factors Orchestrate Biofilm Development in Vibrio parahaemolyticus.. J Bacteriol 202(6) PMID: 31932310
- 8. Zhan X et al.. 2024. A c-di-GMP signaling module controls responses to iron in Pseudomonas aeruginosa.. Nat Commun 15(1):1860 PMID: 38424057
