GO:0004974 leukotriene receptor activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0004974 leukotriene receptor activity describes the molecular function of combining with a leukotriene to initiate a change in cell activity.
• The principal receptors are the cysteinyl leukotriene receptors CYSLTR1 and CYSLTR2, which respond to LTC4, LTD4 and LTE4.
• CYSLTR2 has been structurally resolved in its LTD4-bound active state, revealing the binding pocket and activation mechanism.
• Leukotriene receptor signalling is implicated in asthma and allergy, atherosclerosis, retinal inflammation and triple-negative breast cancer proliferation.
• Cysteinyl leukotriene receptor 1 modulates autophagy and immune cell behaviour in retinal pigment epithelial cells and aged retina.
• CRISPR knockout, point-mutation, knock-in and overexpression models are powerful tools to dissect leukotriene receptor function and drug response.
Description
Leukotriene receptor activity (GO:0004974) is a molecular function in which a receptor protein combines with a leukotriene lipid mediator to initiate a change in cell activity. Leukotrienes are pharmacologically active eicosanoids characterised by a set of three conjugated double bonds, and the cysteinyl leukotrienes LTC4, LTD4 and LTE4 additionally contain a peptide group based on cysteine. This activity is central to inflammatory signalling and is the direct target of widely used anti-asthma and anti-allergy drugs. Researchers study GO:0004974 to understand how lipid mediators are sensed at the plasma membrane and how that sensing is translated into immune, vascular and epithelial responses. The two best-characterised mediators of this function are the cysteinyl leukotriene receptors CYSLTR1 and CYSLTR2, both G protein-coupled receptors that bind cysteinyl leukotrienes with high affinity. Beyond allergy, recent work has shown that CYSLTR2 and the related receptor P2RY6 can sense ceramides to aggravate atherosclerosis, expanding the ligand repertoire associated with this receptor family. In the retina, CYSLTR1 modulates immune cell behaviour, vascularity and proteolytic activity in aged mice, and it regulates autophagic activity in retinal pigment epithelial cells. In oncology, leukotriene receptor antagonists inhibit mitogenic activity in triple-negative breast cancer cells, suggesting that leukotriene receptor activity contributes to proliferation in some tumour contexts. Because the function is druggable and disease-relevant, precise genetic models are needed to separate receptor-specific effects from downstream pathway noise.
leukotriene receptor activity At A Glance
| GO ID | GO:0004974 |
|---|---|
| GO term | leukotriene receptor activity |
| Ontology | molecular_function |
| Synonym | none |
| Definition | Combining with a leukotriene to initiate a change in cell activity; leukotrienes are pharmacologically active substances with a set of three conjugated double bonds, and some contain a peptide group based on cysteine |
| Major function | Ligand-activated receptor signalling in response to leukotrienes such as LTC4, LTD4 and LTE4 |
| Representative receptors | CYSLTR1 and CYSLTR2 |
| Ligand class | Eicosanoid leukotrienes, including cysteinyl leukotrienes |
| Disease relevance | Asthma and allergy, atherosclerosis, retinal inflammation, triple-negative breast cancer |
| Pharmacology | Target of leukotriene receptor antagonists and antiallergy drugs |
What Is GO:0004974?
In our own words, GO:0004974 leukotriene receptor activity is the function performed by a receptor when it binds a leukotriene ligand and, through that binding event, triggers a change in the behaviour of the cell. The definition explicitly requires two elements: combination with a leukotriene, and initiation of a cellular change. Leukotrienes are pharmacologically active substances with a set of three conjugated double bonds, and some contain a peptide group based on cysteine. The function is therefore a ligand-activated receptor activity rather than an enzymatic activity, and it is classified in the molecular_function aspect of the Gene Ontology. Receptors annotated with this activity include the cysteinyl leukotriene receptors CYSLTR1 and CYSLTR2, which are activated by LTC4, LTD4 and LTE4.
Why Is leukotriene receptor activity Important in Cell Biology?
Leukotriene receptor activity matters because it converts a small lipid mediator into a broad cellular response, and because that conversion is directly druggable in human disease. Antagonists of leukotriene receptors are established therapies for asthma and related allergic conditions, which means the molecular function described by GO:0004974 is validated as a clinical target. At the same time, new evidence links these receptors to atherosclerosis through ceramide sensing, to retinal immune and autophagic regulation, and to mitogenic signalling in triple-negative breast cancer. Understanding the precise receptor-ligand interactions and downstream effects is therefore essential for both mechanistic biology and therapeutic development.
• Provides the molecular basis for cysteinyl leukotriene sensing by CYSLTR1 and CYSLTR2.
• Underpins the mechanism of action of leukotriene receptor antagonists used in asthma and allergy.
• Contributes to atherosclerosis through ceramide sensing by CYSLTR2 and P2RY6.
• Modulates retinal immune cells, vascularity and proteolytic activity during ageing.
• Regulates autophagic activity in retinal pigment epithelial cells.
• Supports mitogenic activity in triple-negative breast cancer cells.
• Offers a structural template for rational drug design from the LTD4-bound CYSLTR2 structure.
• Connects lipid mediator biology to inflammation, vascular remodelling and epithelial stress responses.
Molecular Mechanism of leukotriene receptor activity
Ligand recognition and binding
In simple terms: The receptor first has to catch the leukotriene signal.
Leukotriene receptor activity begins with the receptor combining with a leukotriene ligand, as stated in the GO definition. The cysteinyl leukotrienes LTC4, LTD4 and LTE4 are the principal ligands for the cysteinyl leukotriene receptors, and the structural basis of LTD4 recognition by CYSLTR2 has been resolved in the active state. This binding event is the defining molecular step of GO:0004974 and distinguishes it from other lipid receptor activities.
Receptor activation and conformational change
In simple terms: Binding flips the receptor into its active shape.
Once the leukotriene is bound, the receptor undergoes a conformational change that initiates a change in cell activity, which is the second requirement of the GO definition. The LTD4-bound structure of CYSLTR2 provides direct evidence for the active-state conformation adopted upon agonist binding. This activation step is what converts ligand occupancy into a cellular signal.
Cysteinyl leukotriene receptor subtypes
In simple terms: Different receptors respond to the same family of signals.
CYSLTR1 and CYSLTR2 are the major receptors annotated with leukotriene receptor activity. CYSLTR1 has been studied for its effects on retinal immune cells, vascularity and proteolytic activity in aged mice, and for its role in autophagic regulation in retinal pigment epithelial cells. CYSLTR2 has been structurally characterised with LTD4 and has been implicated in ceramide sensing together with P2RY6 in atherosclerosis.
Downstream cellular responses
In simple terms: The signal changes what the cell does.
Activation of leukotriene receptors leads to changes in cell activity that can include immune cell modulation, vascular effects, proteolytic activity and autophagic regulation. In triple-negative breast cancer cells, leukotriene receptor antagonists inhibit mitogenic activity, indicating that receptor activity can feed into proliferation. These diverse outputs illustrate why GO:0004974 is best understood as a signalling function whose consequences are cell-type dependent.
Pharmacological modulation
In simple terms: Drugs can block or tune this receptor activity.
Leukotriene receptor antagonists and related antiallergy drugs act on this molecular function and are used clinically in respiratory and allergic disease. Because the function is defined by ligand binding and receptor activation, antagonists that prevent leukotriene combination directly inhibit GO:0004974. This pharmacological tractability is a major reason the term is important for translational research.
Key Genes Involved in GO:0004974 leukotriene receptor activity
The genes most directly associated with leukotriene receptor activity encode the cysteinyl leukotriene receptors and related pathway components.
| Gene | Major Role | Research Relevance |
|---|---|---|
| CYSLTR1 | Cysteinyl leukotriene receptor 1; binds LTC4, LTD4 and LTE4 | Retinal immune cell modulation, vascularity, proteolytic activity and autophagy |
| CYSLTR2 | Cysteinyl leukotriene receptor 2; binds cysteinyl leukotrienes and senses ceramides | LTD4-bound active-state structure; atherosclerosis via ceramide sensing with P2RY6 |
| P2RY6 | Purinergic receptor implicated with CYSLTR2 in ceramide sensing | Atherosclerosis aggravation in combination with CYSLTR2 |
| ALOX5 | Arachidonate 5-lipoxygenase, upstream in leukotriene biosynthesis | Provides ligand for leukotriene receptor activity |
| ALOX5AP | 5-lipoxygenase activating protein, supports leukotriene synthesis | Upstream regulator of ligand availability |
| LTC4S | Leukotriene C4 synthase, generates cysteinyl leukotrienes | Supplies LTC4 for receptor activation |
| GNAQ | G protein alpha subunit coupled to cysteinyl leukotriene receptors | Downstream signalling from CYSLTR1/CYSLTR2 |
| GNAI1 | G protein alpha i subunit involved in GPCR signalling | Potential downstream effector of leukotriene receptors |
| ARRB1 | Beta-arrestin 1, regulates GPCR desensitisation | Modulates receptor signalling duration |
| ARRB2 | Beta-arrestin 2, regulates GPCR trafficking | Modulates receptor signalling duration |
| MAPK1 | ERK2, downstream kinase in GPCR signalling | Readout of leukotriene receptor activation |
| MAPK3 | ERK1, downstream kinase in GPCR signalling | Readout of leukotriene receptor activation |
| AKT1 | Serine/threonine kinase in proliferation signalling | Linked to mitogenic activity in cancer cells |
| MTOR | mTOR kinase, central regulator of autophagy and growth | Connected to autophagic regulation by CYSLTR1 |
| MAP1LC3B | LC3B, autophagosome marker | Used to monitor autophagy changes after receptor modulation |
| BECN1 | Beclin-1, autophagy regulator | Autophagy pathway component studied with CYSLTR1 |
| NFKB1 | NF-kB subunit, inflammatory transcription factor | Inflammatory signalling downstream of leukotriene receptors |
| IL6 | Interleukin 6, inflammatory cytokine | Inflammatory output associated with leukotriene signalling |
How Is leukotriene receptor activity Regulated?
Leukotriene receptor activity is regulated at multiple levels. Ligand availability depends on upstream leukotriene biosynthesis, and the receptors themselves are subject to desensitisation and trafficking control typical of G protein-coupled receptors. CYSLTR1 modulates autophagic activity in retinal pigment epithelial cells, and this regulation shows chronobiological behaviour during basal and induced autophagy, indicating time-of-day-dependent control. In aged mice, CYSLTR1 modulates retinal immune cells, vascularity and proteolytic activity, showing that receptor function is influenced by the ageing context. Pharmacological antagonists provide an external means of regulating the activity, which is the basis of their clinical use.
leukotriene receptor activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| CYSLTR1 | Retinal inflammation, autophagy regulation, ageing retina | Cysltr1 knockout and overexpression in retinal pigment epithelial cells |
| CYSLTR2 | Atherosclerosis via ceramide sensing | Cysltr2 knockout and point-mutation models in vascular cells |
| P2RY6 | Atherosclerosis in combination with CYSLTR2 | P2ry6 knockout and double-knockout models |
| CYSLTR1/CYSLTR2 | Asthma and allergic disease | Receptor antagonist studies and receptor knockout models |
| CYSLTR1 | Triple-negative breast cancer mitogenic activity | Knockout and overexpression in breast cancer cell lines |
Asthma and allergic disease
Leukotriene receptor activity is a validated target in asthma and allergy, where leukotriene receptor antagonists and related antiallergy drugs are used clinically. Because the molecular function is defined by leukotriene binding and receptor activation, blocking this step directly dampens the downstream allergic response. This makes GO:0004974 one of the clearest examples of a molecular function with an approved pharmacological intervention.
Atherosclerosis and vascular disease
CYSLTR2 and P2RY6 can sense ceramides to aggravate atherosclerosis, linking leukotriene receptor family signalling to vascular pathology. This finding expands the ligand repertoire relevant to this receptor family beyond classical cysteinyl leukotrienes. It also suggests that receptor activity contributes to atherosclerotic plaque progression through lipid sensing mechanisms.
Retinal inflammation and ageing
CYSLTR1 modulates retinal immune cells, vascularity and proteolytic activity in aged mice, and it regulates autophagic activity in retinal pigment epithelial cells. These studies connect leukotriene receptor activity to retinal homeostasis and to age-related changes in the eye. The chronobiological control of autophagy by CYSLTR1 further indicates that receptor activity is integrated with daily physiological rhythms.
Triple-negative breast cancer
Leukotriene receptor antagonists inhibit mitogenic activity in triple-negative breast cancer cells, suggesting that leukotriene receptor activity can support proliferation in this aggressive tumour subtype. This positions the receptor function as a potential experimental target in cancer biology. The finding also motivates genetic models that test causality rather than relying on pharmacological inhibition alone.
From leukotriene receptor activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is CYSLTR1 required for autophagic regulation in retinal pigment epithelial cells? | CYSLTR1 knockout cell line |
| Does CYSLTR2 sense ceramides to aggravate atherosclerosis? | CYSLTR2 knockout and point-mutation models |
| What is the active-state conformation of CYSLTR2 bound to LTD4? | Structural biology with knock-in tagged receptor |
| Does leukotriene receptor activity drive proliferation in triple-negative breast cancer? | CYSLTR1 overexpression and knockout in cancer cells |
| How does CYSLTR1 modulate retinal immune cells and vascularity during ageing? | Aged mouse models with receptor knockout |
| Which downstream kinases are activated by leukotriene receptors? | Knock-in reporter and phospho-kinase profiling models |
How to Study the leukotriene receptor activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Ligand binding assay | Direct leukotriene-receptor combination | Confirming GO:0004974 activity |
| Cryo-EM / structural biology | Receptor active-state conformation | LTD4-bound CYSLTR2 structure |
| Autophagy flux assay | Autophagic activity changes | CYSLTR1 modulation in retinal pigment epithelial cells |
| Retinal imaging | Immune cells, vascularity, proteolytic activity | Aged mouse retina studies |
| Proliferation assay | Mitogenic activity | Triple-negative breast cancer cells |
| Phospho-kinase profiling | Downstream kinase activation | GPCR signalling readouts |
| Knockout / overexpression | Necessity and sufficiency of receptor | Causal testing in cell models |
| Antagonist treatment | Pharmacological inhibition of receptor activity | Asthma and allergy drug studies |
Ligand binding and signalling assays
Ligand binding assays and signalling readouts are used to measure leukotriene receptor activity directly, since the function is defined by combination with a leukotriene and initiation of a cellular change. Structural approaches such as the LTD4-bound CYSLTR2 structure provide atomic-level insight into ligand recognition. These methods are essential for confirming that a candidate receptor performs GO:0004974.
Autophagy and imaging assays
Autophagic activity can be monitored in retinal pigment epithelial cells to assess how CYSLTR1 modulates this process. Imaging of retinal immune cells, vascularity and proteolytic activity in aged mice provides in vivo readouts of receptor function. These assays connect the molecular function to tissue-level phenotypes.
Proliferation and cancer cell assays
Mitogenic activity assays in triple-negative breast cancer cells are used to test whether leukotriene receptor antagonists suppress proliferation. Such experiments link receptor activity to cancer cell growth and help identify contexts where the function is oncogenic. Combining pharmacological and genetic perturbation strengthens causal inference.
Genetic and pharmacological perturbation
Knockout, point-mutation, knock-in and overexpression models allow researchers to test the necessity and sufficiency of leukotriene receptor activity. Pharmacological antagonists provide complementary acute inhibition and are clinically validated. Together, genetic and pharmacological tools define the role of GO:0004974 in disease models.
How CRISPR Can Be Used to Study GO:0004974 leukotriene receptor activity
Knockout
CRISPR knockout of CYSLTR1 or CYSLTR2 removes the receptor and allows researchers to test whether leukotriene receptor activity is required for a given phenotype, such as autophagic regulation or atherosclerosis aggravation. Knockout models are particularly useful when pharmacological antagonists may have off-target effects. They provide clean genetic evidence for the necessity of GO:0004974 in a disease context.
Point Mutation
Point-mutation models can alter specific residues in the ligand-binding pocket or activation switch of cysteinyl leukotriene receptors, informed by the LTD4-bound CYSLTR2 structure. Such models separate ligand binding from downstream activation and help map structure-function relationships. They are valuable for testing whether a disease-associated variant changes receptor activity.
Knock-in
Knock-in of tagged or reporter versions of CYSLTR1 and CYSLTR2 enables tracking of receptor localisation, trafficking and expression in native contexts. Tagged knock-in models can also support structural and biochemical studies of the active receptor. This approach is useful when receptor abundance or localisation, rather than total activity, is the variable of interest.
Overexpression
Overexpression of CYSLTR1 or CYSLTR2 can test sufficiency, for example whether increased receptor levels enhance mitogenic activity in cancer cells or amplify inflammatory signalling. Overexpression models are also used to produce sufficient receptor protein for structural and pharmacological studies. They complement knockout experiments by addressing the opposite direction of perturbation.
How EDITGENE Supports leukotriene receptor activity Research
Researchers studying leukotriene receptor activity-related genes often need to determine whether a candidate gene is causally involved in receptor signalling, disease progression or drug response, and the most rigorous way to answer that question is to build precise genetic models in relevant cell types.
Contact EDITGENE today to design your custom CRISPR model for leukotriene receptor activity research.
Frequently Asked Questions About leukotriene receptor activity
What is leukotriene receptor activity?
Leukotriene receptor activity (GO:0004974) is the molecular function of combining with a leukotriene to initiate a change in cell activity, as defined in the Gene Ontology.
What genes are involved in leukotriene receptor activity?
The principal genes are CYSLTR1 and CYSLTR2, which encode cysteinyl leukotriene receptors, with P2RY6 implicated alongside CYSLTR2 in ceramide sensing.
What is the GO ID for leukotriene receptor activity?
The GO ID is GO:0004974, classified under the molecular_function aspect of the Gene Ontology.
Which ligands activate leukotriene receptors?
Cysteinyl leukotrienes including LTC4, LTD4 and LTE4 activate cysteinyl leukotriene receptors, and ceramides can also be sensed by CYSLTR2 with P2RY6.
How is leukotriene receptor activity studied?
It is studied with ligand binding assays, structural biology, autophagy and imaging assays, proliferation assays, and genetic perturbation using knockout, point-mutation, knock-in and overexpression models.
What diseases are linked to leukotriene receptor activity?
It is linked to asthma and allergy, atherosclerosis, retinal inflammation and ageing, and triple-negative breast cancer mitogenic activity.
Are leukotriene receptor antagonists related to GO:0004974?
Yes, leukotriene receptor antagonists and related antiallergy drugs act on this molecular function and are used clinically in respiratory and allergic disease.
Does CYSLTR1 regulate autophagy?
Yes, CYSLTR1 modulates autophagic activity in retinal pigment epithelial cells, including chronobiological control during basal and induced autophagy.
What is the structure of CYSLTR2 bound to LTD4?
The active-state structure of CYSLTR2 bound to LTD4 has been resolved, providing a structural basis for receptor activation.
Can CRISPR be used to study leukotriene receptor activity?
Yes, CRISPR knockout, point-mutation, knock-in and overexpression models are used to test the necessity and sufficiency of leukotriene receptor activity in disease contexts.
Conclusion
Leukotriene receptor activity (GO:0004974) is a well-defined molecular function that links lipid mediators to cellular responses through receptors such as CYSLTR1 and CYSLTR2. Its clinical relevance is established by leukotriene receptor antagonists used in asthma and allergy, and its broader importance is supported by links to atherosclerosis, retinal biology and cancer proliferation. Precise CRISPR models will be essential to resolve receptor-specific mechanisms and to translate these findings into new therapeutic strategies.
References
- 1. Zhang S et al.. 2025. Sensing ceramides by CYSLTR2 and P2RY6 to aggravate atherosclerosis.. Nature 641(8062):476-485 PMID: 40049228
- 2. Koller A et al.. 2025. Cysteinyl leukotriene receptor 1 modulates retinal immune cells, vascularity and proteolytic activity in aged mice.. Aging (Albany NY) 17(2):308-328 PMID: 39891615
- 3. Koller A et al.. 2020. Cysteinyl leukotriene receptor 1 modulates autophagic activity in retinal pigment epithelial cells.. Sci Rep 10(1):17659 PMID: 33077798
- 4. Koller A et al.. 2021. Chronobiological activity of cysteinyl leukotriene receptor 1 during basal and induced autophagy in the ARPE-19 retinal pigment epithelial cell line.. Aging (Albany NY) 13(24):25670-25693 PMID: 34919533
- 5. Tamada T et al.. 2017. Leukotriene Receptor Antagonists and Antiallergy Drugs.. Handb Exp Pharmacol 237:153-169 PMID: 27826703
- 6. Jiang M et al.. 2025. Structural basis of the cysteinyl leukotriene receptor type 2 activation by LTD4.. Proc Natl Acad Sci U S A 122(15):e2417148122 PMID: 40193607
- 7. Suknuntha K et al.. 2018. Leukotriene Receptor Antagonists Inhibit Mitogenic Activity in Triple Negative Breast Cancer Cells.. Asian Pac J Cancer Prev 19(3):833-837 PMID: 29582642
- 8. Wenzel SE. 1999. Leukotriene receptor antagonists and related compounds.. Can Respir J 6(2):189-93 PMID: 10322101
