GO:0031755 Edg-2 lysophosphatidic acid receptor binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0031755 describes the molecular function of binding to the Edg-2 (LPA1) lysophosphatidic acid receptor, a G-protein-coupled receptor.
• Edg-2/LPA1 is activated by lysophosphatidic acid (LPA) and couples to multiple G proteins to mediate diverse cellular responses.
• The receptor was originally identified as vzg-1/lpA1/edg-2 and is conserved across species, including Xenopus homologs.
• Edg-2 binding can be modulated by subtype-selective antagonists such as Ki16425, which discriminates among EDG-family LPA receptors.
• LPA signaling through Edg-2 influences cell proliferation, survival, migration, and cytoskeletal dynamics, with implications in cancer and fibrosis.
• Studying GO:0031755 requires tools such as receptor binding assays, knockout models, and CRISPR-based editing to dissect ligand-receptor interactions.
Description
GO:0031755, Edg-2 lysophosphatidic acid receptor binding, is a molecular function term that defines the binding of a ligand or protein to the Edg-2 lysophosphatidic acid receptor (also known as LPA1). Edg-2 was initially cloned as vzg-1/lpA1/edg-2 and shown to encode a single receptor that couples to G proteins and mediates multiple cellular responses to lysophosphatidic acid (LPA). This receptor is a member of the EDG family of G-protein-coupled receptors and is activated by LPA, a bioactive phospholipid involved in diverse physiological and pathological processes. Understanding this binding event is crucial for researchers studying LPA signaling, as it represents the first step in receptor activation and downstream signal transduction.
Edg-2 lysophosphatidic acid receptor binding At A Glance
| GO ID | GO:0031755 |
|---|---|
| GO term | Edg-2 lysophosphatidic acid receptor binding |
| Ontology | molecular_function |
| Synonym | Edg-2 lysophosphatidic acid receptor ligand; LPA1 receptor binding |
| Major function | Binding to the Edg-2/LPA1 receptor, mediating LPA-induced signaling |
| Receptor family | G-protein-coupled receptor (GPCR), EDG family |
| Endogenous ligand | Lysophosphatidic acid (LPA) |
| Selective antagonist | Ki16425 (subtype-selective for EDG-family LPA receptors) |
| Cellular responses | Proliferation, survival, migration, cytoskeletal changes |
What Is GO:0031755?
Edg-2 lysophosphatidic acid receptor binding is the molecular function of selectively interacting with the Edg-2 (LPA1) receptor. This binding event typically involves lysophosphatidic acid (LPA) as the endogenous ligand, but can also include synthetic agonists or antagonists that associate with the receptor's ligand-binding pocket. The term encompasses both the ligand-receptor interaction and the binding of accessory proteins that modulate receptor function, such as gelsolin, which has been shown to bind and present LPA to the receptor.
Why Is Edg-2 lysophosphatidic acid receptor binding Important in Cell Biology?
Edg-2 lysophosphatidic acid receptor binding is a critical molecular event that initiates LPA signaling, which regulates a wide array of cellular processes including proliferation, survival, migration, and cytoskeletal reorganization. Dysregulation of this binding and subsequent signaling has been implicated in various diseases, including cancer, fibrosis, and neuropathic pain. Therefore, understanding the molecular details of Edg-2 binding is essential for developing therapeutic strategies that target LPA signaling pathways.
• Initiates LPA-mediated G-protein signaling, affecting multiple downstream pathways.
• Modulates cell proliferation and survival, with implications in cancer progression.
• Regulates cytoskeletal dynamics and cell migration through gelsolin interaction.
• Involved in developmental processes, as shown by Xenopus homologs.
• Targeted by subtype-selective antagonists like Ki16425 for research and therapeutic purposes.
• Plays a role in prostate biology, as Edg-7 (a related receptor) is expressed in prostate.
• Contributes to the pheromone response pathway in yeast when expressed heterologously.
• Serves as a model for studying GPCR-ligand interactions and signal transduction.
• Potential biomarker for diseases with altered LPA metabolism.
• Enables high-throughput screening for receptor modulators.
Molecular Mechanism of Edg-2 lysophosphatidic acid receptor binding
Ligand Recognition and Binding
In simple terms: The receptor grabs LPA from the environment.
Edg-2/LPA1 binds lysophosphatidic acid (LPA) with high specificity, as demonstrated by the receptor's ability to couple to G proteins and mediate cellular responses only in the presence of LPA. The binding involves interaction with the receptor's extracellular loops and transmembrane domains, leading to conformational changes that activate G proteins.
G-Protein Coupling and Activation
In simple terms: Once LPA binds, the receptor turns on G proteins inside the cell.
Upon LPA binding, Edg-2 couples to G proteins, including Gi, Gq, and G12/13, to initiate multiple signaling cascades. This coupling is selective, as Edg-2 does not respond to sphingosine-1-phosphate, highlighting the specificity of the binding event.
Modulation by Accessory Proteins
In simple terms: Other proteins can help present LPA to the receptor.
Gelsolin, an actin-binding protein, has been shown to bind LPA and facilitate its presentation to Edg-2, enhancing receptor activation. This suggests that the binding function of GO:0031755 can be regulated by extracellular or membrane-associated partners.
Pharmacological Interference
In simple terms: Drugs can block the receptor to stop signaling.
Subtype-selective antagonists such as Ki16425 inhibit LPA binding to EDG-family receptors, including Edg-2, by competing for the ligand-binding site. This provides a tool to study the specific contribution of Edg-2 binding in cellular processes.
Evolutionary Conservation
In simple terms: Similar receptors exist in other species.
Xenopus homologs of mammalian LPA1/EDG-2 function as LPA receptors in oocytes and mammalian cells, indicating that the binding mechanism is evolutionarily conserved. This conservation allows the use of model organisms to study GO:0031755.
Key Genes Involved in GO:0031755 Edg-2 lysophosphatidic acid receptor binding
The following genes and proteins are directly involved in or regulate Edg-2 lysophosphatidic acid receptor binding.
| Gene | Major Role | Research Relevance |
|---|---|---|
| LPAR1 (EDG-2) | Encodes the Edg-2/LPA1 receptor; binds LPA | Primary receptor for GO:0031755; knockout models available |
| LPA | Endogenous ligand for Edg-2 | Bioactive lipid; binding initiates signaling |
| GNAI1 | G protein subunit that couples to Edg-2 | Mediates downstream signaling |
| GNAQ | G protein subunit that couples to Edg-2 | Activates PLC and calcium signaling |
| GNA12 | G protein subunit that couples to Edg-2 | Activates Rho GTPase pathways |
| GSN (Gelsolin) | Binds LPA and presents it to Edg-2 | Modulates ligand availability |
| LPAR2 (EDG-4) | Related LPA receptor | Can be compared to Edg-2 for specificity |
| LPAR3 (EDG-7) | Related LPA receptor | Expressed in prostate; distinct from Edg-2 |
| LPAR4 (P2Y9/GPR23) | Novel LPA receptor distant from EDG family | Provides evolutionary context |
| LPAR5 | LPA receptor | Potential heterodimerization partner |
| LPAR6 | LPA receptor | May share downstream pathways |
| Ki16425 | Subtype-selective antagonist | Chemical tool to inhibit Edg-2 binding |
| Vzg-1 | Xenopus homolog of Edg-2 | Model for developmental studies |
| Edg-2 (yeast) | Heterologous expression in yeast | Used to study pheromone response coupling |
| RhoA | Downstream effector of G12/13 | Regulates cytoskeletal changes |
| Rac1 | Downstream effector of Gi | Mediates cell migration |
| PLCβ | Downstream effector of Gq | Produces IP3 and DAG |
How Is Edg-2 lysophosphatidic acid receptor binding Regulated?
The binding function of Edg-2 is regulated at multiple levels. Receptor expression levels can be modulated by transcriptional and post-transcriptional mechanisms, as seen in prostate cancer where Edg-7 is upregulated. Ligand availability is controlled by enzymes that synthesize or degrade LPA, such as autotaxin and lipid phosphate phosphatases. Additionally, accessory proteins like gelsolin can enhance LPA presentation to the receptor. Pharmacological agents such as Ki16425 can competitively inhibit binding, providing a means to regulate the pathway exogenously.
Edg-2 lysophosphatidic acid receptor binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| LPAR1 (EDG-2) | Cancer, fibrosis, neuropathic pain | Knockout mouse, CRISPR KO cell lines |
| GSN (Gelsolin) | Fibrosis, amyloidosis | Overexpression and KO models |
| LPAR3 (EDG-7) | Prostate cancer | Prostate cancer cell lines with knockdown |
| LPAR4 (P2Y9) | Developmental disorders | Zebrafish or Xenopus models |
| LPAR2 (EDG-4) | Inflammation | LPS-induced inflammation models |
Cancer
Edg-2/LPA1 binding and signaling are implicated in cancer progression, including cell proliferation, survival, and migration. Overexpression of LPA receptors, including Edg-2, has been observed in various cancers, and LPA promotes tumorigenesis through multiple signaling pathways. The binding event is a potential therapeutic target, with antagonists like Ki16425 showing efficacy in preclinical models.
Fibrosis
LPA signaling through Edg-2 contributes to fibrosis by promoting fibroblast proliferation and collagen deposition. Gelsolin-mediated LPA presentation may exacerbate fibrotic responses. Targeting Edg-2 binding could attenuate fibrosis in organs such as lung and liver.
Neuropathic Pain
LPA signaling via Edg-2 has been linked to neuropathic pain development. Binding of LPA to Edg-2 in dorsal root ganglia activates downstream pathways that lead to pain hypersensitivity. Antagonists that block this binding may offer therapeutic relief.
Developmental Disorders
Edg-2 is essential for normal development, as shown by Xenopus homologs that function in oocytes and embryos. Disruption of LPA binding may lead to developmental abnormalities, although specific human disorders are still being investigated.
From Edg-2 lysophosphatidic acid receptor binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does Edg-2 binding mediate LPA-induced proliferation? | LPAR1 knockout cell lines (e.g., CRISPR KO) |
| What is the role of specific residues in LPA binding? | Point-mutation knock-in of LPAR1 |
| How does Edg-2 binding affect downstream G-protein activation? | Tagged knock-in of LPAR1 with BRET biosensors |
| Can overexpression of Edg-2 enhance LPA sensitivity? | Overexpression of LPAR1 in HEK293 cells |
| What is the effect of Edg-2 binding on cell migration? | Knockout of LPAR1 in cancer cell lines |
| How does gelsolin modulate LPA presentation to Edg-2? | Gelsolin KO and overexpression models |
How to Study the Edg-2 lysophosphatidic acid receptor binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Radioligand binding | Direct binding affinity (Kd) of LPA to Edg-2 | Screening for receptor antagonists |
| GTPγS binding | G-protein activation | Functional coupling of Edg-2 to Gi/Gq |
| BRET biosensor | Real-time GPCR activation | Kinetics of LPA-induced signaling |
| CRISPR knockout screen | Genes required for Edg-2 binding/signaling | Identification of novel regulators |
| Live-cell imaging | Receptor internalization and trafficking | Visualization of binding dynamics |
| Co-immunoprecipitation | Protein-protein interactions with Edg-2 | Discovery of accessory proteins like gelsolin |
| RNA-seq | Transcriptional changes upon LPA stimulation | Downstream gene expression profiling |
| Proteomics | Post-translational modifications of Edg-2 | Phosphorylation site mapping |
Receptor Binding Assays
Radioligand binding assays using [3H]-LPA or fluorescently labeled LPA can directly measure binding affinity and kinetics to Edg-2. These assays are essential for characterizing agonists and antagonists.
G-Protein Activation Assays
GTPγS binding or BRET-based biosensors can detect G-protein activation following LPA binding to Edg-2. These methods quantify the functional consequence of the binding event.
CRISPR-Based Genetic Screens
Genome-wide CRISPR knockout screens can identify genes that regulate Edg-2 binding or LPA signaling. Such screens have been used to uncover novel modulators of GPCR pathways.
Live-Cell Imaging
Fluorescently tagged Edg-2 and LPA analogs enable real-time visualization of binding and internalization in live cells. This provides spatiotemporal insights into receptor dynamics.
How CRISPR Can Be Used to Study GO:0031755 Edg-2 lysophosphatidic acid receptor binding
Knockout
CRISPR knockout of LPAR1 (EDG-2) eliminates receptor expression, allowing researchers to study the loss of LPA binding and its downstream effects. This is useful for validating the specificity of LPA responses and identifying compensatory receptors.
Point Mutation
Introducing point mutations in the ligand-binding pocket of Edg-2 can dissect the molecular determinants of LPA binding. For example, mutating residues predicted to interact with the phosphate headgroup can abolish binding, as shown for related GPCRs.
Knock-in
Knock-in of tagged Edg-2 (e.g., HA or GFP) enables visualization and biochemical isolation of the receptor. This approach helps track receptor localization and interaction partners in native contexts.
Overexpression
Overexpression of LPAR1 in cell lines such as HEK293 or CHO cells enhances LPA binding capacity, facilitating biochemical assays and high-throughput screening for modulators.
How EDITGENE Supports Edg-2 lysophosphatidic acid receptor binding Research
Researchers studying Edg-2 lysophosphatidic acid receptor binding-related genes often need to determine whether a candidate gene is causally involved in receptor function, signaling, or disease. EDITGENE provides a comprehensive suite of CRISPR services to accelerate such investigations.
Contact EDITGENE today to design your custom CRISPR model for Edg-2 lysophosphatidic acid receptor binding research.
Frequently Asked Questions About Edg-2 lysophosphatidic acid receptor binding
What is GO:0031755?
GO:0031755 is the Gene Ontology molecular function term for Edg-2 lysophosphatidic acid receptor binding, describing the binding to the Edg-2/LPA1 receptor.
What genes are involved in Edg-2 lysophosphatidic acid receptor binding?
The primary gene is LPAR1 (EDG-2), which encodes the receptor. Other genes include GNAI1, GNAQ, GNA12, and GSN (gelsolin) that modulate binding or signaling.
What is the function of Edg-2?
Edg-2 (LPA1) is a G-protein-coupled receptor that binds lysophosphatidic acid (LPA) and mediates multiple cellular responses, including proliferation, survival, and migration.
How is Edg-2 binding studied?
Common methods include radioligand binding assays, GTPγS binding, BRET biosensors, and CRISPR knockout models.
What diseases are associated with Edg-2 binding?
Edg-2 binding and signaling are implicated in cancer, fibrosis, neuropathic pain, and developmental disorders.
What is Ki16425?
Ki16425 is a subtype-selective antagonist for EDG-family LPA receptors, including Edg-2, used to inhibit LPA binding.
Is Edg-2 conserved across species?
Yes, Xenopus homologs of mammalian LPA1/EDG-2 function as LPA receptors, indicating evolutionary conservation.
Can CRISPR be used to study Edg-2 binding?
Yes, CRISPR knockout, point mutation, and knock-in models are powerful tools to dissect Edg-2 binding and signaling.
What is the role of gelsolin in Edg-2 binding?
Gelsolin binds LPA and presents it to Edg-2, enhancing receptor activation.
How does LPA activate Edg-2?
LPA binds to the extracellular domain of Edg-2, inducing conformational changes that activate G proteins and downstream signaling.
Conclusion
GO:0031755, Edg-2 lysophosphatidic acid receptor binding, represents a fundamental molecular interaction that triggers diverse cellular responses through LPA signaling. Understanding this binding event is crucial for elucidating its roles in physiology and disease, and for developing targeted therapies. With advanced CRISPR tools and bioinformatics, researchers can now dissect the precise mechanisms and identify novel modulators of this pathway.
References
- 1. Fukushima N et al.. 1998. A single receptor encoded by vzg-1/lpA1/edg-2 couples to G proteins and mediates multiple cellular responses to lysophosphatidic acid.. Proc Natl Acad Sci U S A 95(11):6151-6 PMID: 9600933
- 2. Erickson JR et al.. 1998. Edg-2/Vzg-1 couples to the yeast pheromone response pathway selectively in response to lysophosphatidic acid.. J Biol Chem 273(3):1506-10 PMID: 9430689
- 3. Goetzl EJ et al.. 2000. Gelsolin binding and cellular presentation of lysophosphatidic acid.. J Biol Chem 275(19):14573-8 PMID: 10799543
- 4. Im DS et al.. 2000. Molecular cloning and characterization of a lysophosphatidic acid receptor, Edg-7, expressed in prostate.. Mol Pharmacol 57(4):753-9 PMID: 10727522
- 5. Ohta H et al.. 2003. Ki16425, a subtype-selective antagonist for EDG-family lysophosphatidic acid receptors.. Mol Pharmacol 64(4):994-1005 PMID: 14500756
- 6. Peyruchaud O et al.. 2000. Differential stimulation of signaling pathways initiated by Edg-2 in response to lysophosphatidic acid or sphingosine-1-phosphate.. Cell Mol Life Sci 57(7):1109-16 PMID: 10961347
- 7. Noguchi K et al.. 2003. Identification of p2y9/GPR23 as a novel G protein-coupled receptor for lysophosphatidic acid, structurally distant from the Edg family.. J Biol Chem 278(28):25600-6 PMID: 12724320
- 8. Kimura Y et al.. 2001. Two novel Xenopus homologs of mammalian LP(A1)/EDG-2 function as lysophosphatidic acid receptors in Xenopus oocytes and mammalian cells.. J Biol Chem 276(18):15208-15 PMID: 11278944
