GO:0050544 arachidonate binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0050544 arachidonate binding is a molecular function defined as binding to arachidonic acid, the all-Z-(5,8,11,14)-isomer of a 20-carbon fatty acid with four double bonds.
• Arachidonate binding is not passive: it can be covalent, as shown for G protein alpha subunits in human platelets, where arachidonate is attached to the protein.
• Membrane and soluble proteins differ widely in arachidonate binding capacity; human red cell membranes bind arachidonate and palmitate with different capacities, and bovine serum albumin binds arachidonate and oleate with distinct affinities.
• Arachidonate binding proteins include alpha-fetoprotein, which shows binding specificity for arachidonate, bilirubin, docosahexaenoate, and palmitate, and a neutrophil cytosolic GTP-binding protein involved in NADPH oxidase regulation.
• Arachidonate and its metabolites act through receptors such as lipoxin receptors, linking arachidonate binding to resolution of inflammation.
• Dysregulated arachidonate metabolism and binding are relevant to inflammatory, infectious, and metabolic disease contexts, including macrophage responses to Mycobacterium tuberculosis.
Description
Arachidonate binding (GO:0050544) is the molecular function of selectively interacting with arachidonic acid, a straight-chain 20-carbon fatty acid containing four double bonds in the all-Z-(5,8,11,14) configuration. Arachidonic acid is a central precursor in lipid signaling and is released from membrane phospholipids to serve as a substrate for cyclooxygenases, lipoxygenases, and cytochrome P450 enzymes, making its binding to proteins a key control point in inflammation and cell signaling. Because arachidonate is hydrophobic and membrane-associated, proteins that bind it must present suitable hydrophobic pockets or covalent attachment sites, and the functional consequences of binding range from transport and sequestration to allosteric regulation and covalent modification. Researchers study arachidonate binding to understand how lipid signals are generated, how they are terminated, and how they are interpreted by downstream receptors such as lipoxin receptors. The term is therefore relevant to immunology, neuroscience, vascular biology, and infectious disease, where arachidonate-derived mediators shape host responses. In practice, arachidonate binding is assayed with radiolabeled or fluorescent fatty acid ligands, spin-label methods, and membrane-binding assays, and it is increasingly interpreted alongside genetic perturbation of candidate binding proteins.
arachidonate binding At A Glance
| GO ID | GO:0050544 |
|---|---|
| GO term | arachidonate binding |
| Ontology | molecular_function |
| Synonym | arachidonic acid binding |
| Definition | Binding to arachidonic acid, a straight chain fatty acid with 20 carbon atoms and four double bonds per molecule; the all-Z-(5,8,11,14)-isomer. |
| Major function | Selective recognition and interaction with arachidonic acid for transport, signaling, or covalent modification. |
| Binding mode | Can be non-covalent, as with serum albumin and membrane sites, or covalent, as with G protein alpha subunits. |
| Representative binders | G protein alpha subunits, serum albumin, alpha-fetoprotein, red cell membrane proteins, and a neutrophil cytosolic GTP-binding protein. |
| Related biology | Arachidonic acid metabolism and eicosanoid signaling, including lipoxin receptor pathways. |
What Is GO:0050544?
In the Gene Ontology, GO:0050544 arachidonate binding is a molecular function describing the selective interaction of a gene product with arachidonic acid, defined as a straight chain fatty acid with 20 carbon atoms and four double bonds per molecule, specifically the all-Z-(5,8,11,14)-isomer. The synonym arachidonic acid binding is used interchangeably. This function does not imply catalysis; it describes the binding event itself, which may be non-covalent or covalent, and may occur at membranes, in the cytosol, or on secreted carrier proteins.
Why Is arachidonate binding Important in Cell Biology?
Arachidonate binding matters because arachidonic acid is the precursor of a large family of lipid mediators, and the proteins that bind it determine whether the fatty acid is stored, transported, converted enzymatically, or used as a covalent modifier. Covalent arachidonate attachment to G protein alpha subunits in human platelets demonstrates that binding can directly alter signaling proteins, while binding to albumin and alpha-fetoprotein illustrates how soluble carriers control the availability of free arachidonate. Because arachidonate-derived mediators participate in inflammation and its resolution through receptors such as lipoxin receptors, and because lipid handling influences infectious disease outcomes in macrophages, arachidonate binding is a functionally important node for both basic and translational research.
• Arachidonic acid is a precursor of prostaglandins, leukotrienes, and lipoxins, so arachidonate binding controls substrate availability for eicosanoid synthesis.
• Covalent arachidonate binding to G protein alpha subunits in human platelets links the lipid directly to heterotrimeric G protein signaling.
• Serum albumin binds arachidonate and oleate, indicating that arachidonate binding contributes to fatty acid transport and buffering in circulation.
• Alpha-fetoprotein binds arachidonate with specificity relative to other fatty acids, showing that arachidonate binding can be selective in a carrier protein context.
• Human red cell membranes display different arachidonate and palmitate binding capacities, suggesting membrane composition influences arachidonate binding.
• A neutrophil cytosolic GTP-binding protein involved in NADPH oxidase regulation is a relevant arachidonate-binding context for innate immune cell function.
• Lipoxin receptors mediate responses to arachidonate-derived lipoxins, connecting arachidonate binding to resolution of inflammation.
• Macrophage lipid handling and ferroptosis pathways intersect with arachidonate metabolism in Mycobacterium tuberculosis infection.
• Arachidonate binding proteins are candidate targets for anti-inflammatory and metabolic research.
• Assays for arachidonate binding provide a route to identify and validate new lipid-binding proteins.
Molecular Mechanism of arachidonate binding
Recognition of the all-Z-(5,8,11,14) arachidonate isomer
In simple terms: The protein must recognize a specific 20-carbon fatty acid shape with four double bonds.
Arachidonate binding begins with molecular recognition of arachidonic acid, defined as a straight chain fatty acid with 20 carbon atoms and four double bonds per molecule in the all-Z-(5,8,11,14) configuration. This definition distinguishes arachidonate from saturated and monounsaturated fatty acids such as palmitate and oleate, and binding proteins can discriminate among them: human red cell membranes show different arachidonate and palmitate binding capacities, and bovine serum albumin binds arachidonate and oleate with distinct behavior. Alpha-fetoprotein also displays binding specificity for arachidonate relative to docosahexaenoate and palmitate in spin label studies. Together these observations indicate that arachidonate binding depends on structural features of the ligand, including chain length and unsaturation.
Non-covalent binding to carrier and membrane proteins
In simple terms: Many proteins hold arachidonate reversibly without changing it chemically.
A major mode of arachidonate binding is reversible, non-covalent association with carrier proteins or membrane sites. Bovine serum albumin binds arachidonate and oleate, consistent with a transport and buffering role for this abundant plasma protein. Human red cell membranes exhibit arachidonate and palmitate binding capacities, indicating that membrane-associated binding sites contribute to arachidonate handling at the cell surface. Alpha-fetoprotein binds arachidonate with specificity, further supporting the existence of defined non-covalent binding pockets for this fatty acid. These examples show that arachidonate binding can occur in soluble and membrane environments without covalent modification of the protein.
Covalent attachment of arachidonate to G protein alpha subunits
In simple terms: Some proteins form a stable chemical bond with arachidonate.
Arachidonate binding is not limited to reversible interactions. Covalent binding of arachidonate to G protein alpha subunits of human platelets has been demonstrated, establishing that arachidonate can be attached to a signaling protein through a covalent linkage. This finding places arachidonate binding within the broader context of lipid modification of G proteins and suggests that covalent arachidonylation can influence G protein function. Because G protein alpha subunits are central transducers of extracellular signals, covalent arachidonate binding represents a mechanism by which a lipid can directly modify signal transduction.
Arachidonate binding in innate immune cells
In simple terms: Immune cells use arachidonate-binding proteins to control oxidative responses.
In neutrophils, a GTP-binding protein located in the cytosolic fraction regulates cell-free NADPH oxidase activation, providing a context in which arachidonate-binding or arachidonate-responsive proteins participate in innate immune signaling. Macrophage responses to Mycobacterium tuberculosis involve modulation of ferroptosis through a microRNA/SAT1 axis, a pathway that intersects with lipid metabolism and arachidonate handling. These findings link arachidonate binding to host defense and to the regulation of oxidative and lipid-dependent cell death programs.
Downstream signaling through arachidonate-derived mediators
In simple terms: Once bound or released, arachidonate is converted into signals that act on receptors.
Arachidonate binding is functionally coupled to arachidonic acid metabolism, in which the fatty acid is converted into prostaglandins, leukotrienes, and lipoxins. Lipoxin receptors mediate cellular responses to arachidonate-derived lipoxins, connecting arachidonate binding and release to resolution of inflammation. Thus, proteins that bind arachidonate can influence the availability of substrate for eicosanoid synthesis and, indirectly, the activation of receptors such as lipoxin receptors.
Key Genes Involved in GO:0050544 arachidonate binding
The following genes and proteins are representative arachidonate-binding or arachidonate-handling factors supported by the cited literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| GNA family alpha subunits | Covalent arachidonate binding in human platelets | Links arachidonate to G protein signaling |
| ALB | Binds arachidonate and oleate in serum | Model for fatty acid transport and buffering |
| AFP | Binds arachidonate with specificity | Spin label studies of fatty acid binding specificity |
| Red cell membrane proteins | Arachidonate and palmitate binding capacities | Membrane binding site analysis |
| Neutrophil cytosolic GTP-binding protein | Regulates NADPH oxidase activation | Innate immune oxidase regulation |
| SAT1 | Modulates ferroptosis in macrophages | Lipid and infection biology |
| Lipoxin receptors (e.g., FPR2/ALX) | Mediate lipoxin responses | Resolution of inflammation |
| Cyclooxygenases | Convert arachidonate to prostaglandins | Eicosanoid biosynthesis |
| Lipoxygenases | Convert arachidonate to leukotrienes and lipoxins | Inflammatory mediator synthesis |
| Cytochrome P450 enzymes | Oxidize arachidonate | Eicosanoid diversity |
| Phospholipase A2 enzymes | Release arachidonate from membranes | Substrate supply for binding |
| Prostaglandin synthases | Terminal eicosanoid synthesis | Downstream of arachidonate release |
| Leukotriene synthases | Leukotriene synthesis | Inflammatory signaling |
| FPR2/ALX | Lipoxin receptor | Anti-inflammatory signaling |
| GPR32 | Lipoxin receptor | Resolution pathways |
| miR-515-5p | Modulates SAT1 axis | Macrophage infection response |
| miR-519e-5p | Modulates SAT1 axis | Macrophage infection response |
How Is arachidonate binding Regulated?
Arachidonate binding is regulated by the availability of free arachidonic acid, which depends on phospholipase-mediated release from membrane phospholipids and on the balance between binding proteins and metabolizing enzymes. Carrier proteins such as albumin and alpha-fetoprotein can sequester arachidonate and thereby modulate its effective concentration, while membrane binding sites contribute to local retention and presentation. Covalent attachment to G protein alpha subunits represents a distinct regulatory mode in which the lipid becomes a stable modification of a signaling protein. In innate immune cells, pathways involving a neutrophil cytosolic GTP-binding protein and the SAT1 axis influence arachidonate-dependent oxidative and ferroptotic responses. Downstream, lipoxin receptors mediate the biological actions of arachidonate-derived lipoxins, providing feedback control of inflammatory signaling.
arachidonate binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| GNA family alpha subunits | Platelet signaling and thrombosis | Knockout or point-mutation platelet cell models |
| ALB | Fatty acid transport and inflammation | Knock-in or overexpression in hepatic cell lines |
| AFP | Fatty acid binding in development and cancer | Overexpression and binding assays |
| SAT1 | Macrophage ferroptosis in tuberculosis | Knockout macrophages with infection challenge |
| FPR2/ALX | Resolution of inflammation | Knockout and knock-in reporter models |
Inflammation and resolution
Arachidonate binding controls the availability of arachidonic acid for conversion into prostaglandins, leukotrienes, and lipoxins, which are central mediators of inflammation and its resolution. Lipoxin receptors mediate responses to arachidonate-derived lipoxins, and their activation is associated with anti-inflammatory and pro-resolving signaling. Proteins that bind arachidonate, including albumin and alpha-fetoprotein, can influence the free arachidonate pool and thus the intensity of eicosanoid signaling. Consequently, dysregulated arachidonate binding may contribute to chronic inflammatory states.
Infectious disease and macrophage biology
Macrophage responses to Mycobacterium tuberculosis involve modulation of ferroptosis through a microRNA/SAT1 axis, a pathway that intersects with lipid metabolism and arachidonate handling. A neutrophil cytosolic GTP-binding protein that regulates NADPH oxidase activation provides another link between arachidonate-binding contexts and innate immune oxidative responses. These findings suggest that arachidonate binding and metabolism influence host-pathogen interactions in macrophages and neutrophils.
Platelet and vascular signaling
Covalent binding of arachidonate to G protein alpha subunits of human platelets demonstrates a direct connection between arachidonate binding and platelet signal transduction. Because platelets are key effectors in thrombosis and vascular inflammation, and because arachidonate is a substrate for thromboxane and related eicosanoids, arachidonate binding proteins are relevant to vascular biology.
From arachidonate binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is a candidate gene required for arachidonate binding? | CRISPR knockout cell line followed by binding assay |
| Does a specific residue mediate arachidonate binding? | Point-mutation knock-in of the candidate residue |
| Can a binding-deficient allele be tracked in cells? | Tagged knock-in with fluorescent or affinity tag |
| Does overexpression change arachidonate-dependent signaling? | Overexpression cell model with lipid mediator readouts |
| Which proteins bind arachidonate in a given cell type? | Proteomics or lipid-protein crosslinking in wild-type and knockout cells |
| Does arachidonate binding regulate innate immune responses? | Knockout macrophages or neutrophils with infection or oxidase assays |
How to Study the arachidonate binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Radiolabeled arachidonate binding | Direct binding capacity | Membrane and protein binding studies |
| Fluorescent fatty acid binding | Binding affinity and specificity | Carrier protein characterization |
| Spin label spectroscopy | Binding specificity and site environment | Alpha-fetoprotein and related proteins |
| Mass spectrometry | Covalent arachidonate adducts | G protein modification mapping |
| Eicosanoid profiling | Downstream metabolite production | Inflammation and resolution studies |
| Lipoxin receptor signaling assays | Receptor activation | Resolution of inflammation |
| NADPH oxidase activation assay | Oxidative burst regulation | Neutrophil cytosolic factor studies |
| Macrophage infection models | Host-pathogen lipid responses | Mycobacterium tuberculosis studies |
Radiolabeled and fluorescent arachidonate binding assays
Direct binding of arachidonate can be measured using radiolabeled or fluorescent fatty acid ligands incubated with purified proteins, membranes, or cells. Human red cell membrane studies compared arachidonate and palmitate binding capacities, illustrating how such assays distinguish fatty acid specificity. Bovine serum albumin binding of arachidonate and oleate has also been characterized, providing a reference for soluble carrier proteins.
Spin label and spectroscopic methods
Spin label studies have been used to assess the binding specificity of alpha-fetoprotein for arachidonate, bilirubin, docosahexaenoate, and palmitate. Spectroscopic and biophysical approaches complement radioligand assays by reporting on conformational changes and binding site occupancy.
Covalent modification detection
Covalent arachidonate binding to G protein alpha subunits of human platelets was demonstrated by biochemical detection of the lipid-protein adduct. Mass spectrometry and radiolabeling can be used to identify covalent arachidonate attachment sites on candidate proteins.
Functional and pathway readouts
Because arachidonate binding is coupled to eicosanoid synthesis and receptor signaling, functional readouts include measurement of prostaglandins, leukotrienes, and lipoxins, as well as lipoxin receptor-dependent responses. Innate immune assays such as NADPH oxidase activation and macrophage infection models provide context-dependent functional endpoints.
How CRISPR Can Be Used to Study GO:0050544 arachidonate binding
Knockout
CRISPR knockout of candidate arachidonate-binding genes allows researchers to test whether the gene product is required for arachidonate binding or for downstream eicosanoid production. For example, knocking out a G protein alpha subunit or a carrier protein candidate can be combined with radiolabeled arachidonate binding assays to quantify loss of binding. Knockout macrophages or neutrophils can be used to assess arachidonate-dependent innate immune functions such as NADPH oxidase activation.
Point Mutation
Point-mutation knock-in can be used to disrupt a specific residue predicted to contact arachidonate, thereby testing the structural basis of binding without deleting the entire protein. This approach is suited to proteins such as alpha-fetoprotein or G protein alpha subunits where binding specificity has been documented. Binding-deficient point mutants can then be compared with wild-type proteins in lipid binding and signaling assays.
Knock-in
Knock-in of tagged alleles, such as fluorescent or affinity tags, enables tracking of arachidonate-binding proteins in live cells and in biochemical pulldowns. Tagged knock-in models can be used to localize candidate proteins to membranes or cytosol and to correlate localization with arachidonate binding capacity. Knock-in of disease-associated variants can also be used to test whether arachidonate binding is altered.
Overexpression
Overexpression of a candidate arachidonate-binding protein can amplify binding signals and downstream lipid mediator production, making it useful for gain-of-function studies. Overexpression models can be combined with eicosanoid profiling and lipoxin receptor signaling assays to test whether increased arachidonate binding enhances or suppresses inflammatory outputs. Overexpression in macrophage or neutrophil backgrounds can reveal effects on infection and oxidative responses.
How EDITGENE Supports arachidonate binding Research
Researchers studying arachidonate binding-related genes often need to determine whether a candidate gene is causally involved in lipid recognition, transport, or downstream signaling. EDITGENE provides CRISPR-based cell model services that allow precise perturbation of candidate arachidonate-binding genes, from complete knockout to single-residue point mutation, tagged knock-in, and controlled overexpression, supported by library screening and bioinformatics for pathway-level interpretation.
Contact EDITGENE today to design your custom CRISPR model for arachidonate binding research.
Frequently Asked Questions About arachidonate binding
What is arachidonate binding?
Arachidonate binding is the molecular function GO:0050544, defined as binding to arachidonic acid, a straight chain fatty acid with 20 carbon atoms and four double bonds per molecule in the all-Z-(5,8,11,14) configuration.
What is the GO ID for arachidonate binding?
The Gene Ontology identifier is GO:0050544, with the synonym arachidonic acid binding.
What genes are involved in arachidonate binding?
Representative genes and proteins include G protein alpha subunits that covalently bind arachidonate, albumin, alpha-fetoprotein, red cell membrane proteins, and a neutrophil cytosolic GTP-binding protein.
Is arachidonate binding covalent or non-covalent?
Both modes exist: albumin and alpha-fetoprotein bind arachidonate non-covalently, while G protein alpha subunits of human platelets can bind arachidonate covalently.
Which proteins bind arachidonic acid?
Examples include serum albumin, alpha-fetoprotein, red cell membrane proteins, G protein alpha subunits, and a neutrophil cytosolic GTP-binding protein involved in NADPH oxidase regulation.
How is arachidonate binding measured?
Common methods include radiolabeled or fluorescent arachidonate binding assays, spin label spectroscopy, mass spectrometry for covalent adducts, and downstream eicosanoid profiling.
Why is arachidonate binding important in inflammation?
Arachidonic acid is converted into prostaglandins, leukotrienes, and lipoxins, and lipoxin receptors mediate pro-resolving signals, so binding proteins control the availability of these mediators.
Does arachidonate binding matter in infectious disease?
Yes, macrophage responses to Mycobacterium tuberculosis involve lipid and ferroptosis pathways, and neutrophil oxidase regulation involves arachidonate-related GTP-binding proteins.
Can CRISPR be used to study arachidonate binding?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models can be used to test whether specific genes and residues are required for arachidonate binding and downstream signaling.
What cell models are suitable for arachidonate binding research?
Platelet, hepatic, macrophage, neutrophil, and red cell membrane systems have been used in the cited literature, and can be adapted for CRISPR perturbation studies.
Conclusion
GO:0050544 arachidonate binding defines a molecular function that connects a specific 20-carbon, four-double-bond fatty acid to diverse proteins, including covalent targets such as G protein alpha subunits and non-covalent carriers such as albumin and alpha-fetoprotein. Because arachidonic acid is the precursor of prostaglandins, leukotrienes, and lipoxins, arachidonate binding sits upstream of major inflammatory and pro-resolving pathways. CRISPR-based knockout, point-mutation, knock-in, and overexpression models provide a direct route to test the causal roles of candidate arachidonate-binding genes in these pathways.
References
- 1. Hallak H et al.. 1994. Covalent binding of arachidonate to G protein alpha subunits of human platelets.. J Biol Chem 269(7):4713-6 PMID: 8106438
- 2. Needleman P et al.. 1986. Arachidonic acid metabolism.. Annu Rev Biochem 55:69-102 PMID: 3017195
- 3. Bojesen IN et al.. 1994. Different arachidonate and palmitate binding capacities of the human red cell membrane.. J Membr Biol 142(1):113-6 PMID: 7707348
- 4. Gabig TG et al.. 1990. A neutrophil GTP-binding protein that regulates cell free NADPH oxidase activation is located in the cytosolic fraction.. J Immunol 145(3):945-51 PMID: 2115550
- 5. Bojesen IN et al.. 1994. Binding of arachidonate and oleate to bovine serum albumin.. J Lipid Res 35(5):770-8 PMID: 8071600
- 6. Li Y et al.. 2025. LncRNA-CFTBS enhances Mycobacterium tuberculosis survival in macrophages by modulating ferroptosis through the miR-515-5p/miR-519e-5p/SAT1 axis.. Virulence 16(1):2545563 PMID: 41075263
- 7. Hsia JC et al.. 1980. alpha-fetoprotein binding specificity for arachidonate, bilirubin, docosahexaenoate, and palmitate. A spin label study.. J Biol Chem 255(9):4224-7 PMID: 6154708
- 8. Romano M et al.. 2007. Lipoxin receptors.. ScientificWorldJournal 7:1393-412 PMID: 17767357
