GO:0001604 urotensin II receptor activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0001604 defines the molecular function of combining with urotensin II (UII) to initiate a change in cell activity, typically through the G protein-coupled receptor UT (gene UTS2R).
• The urotensin II receptor (UT) is a class A GPCR that couples to Gq/11 and other G proteins, mobilizing calcium and activating downstream signaling.
• UT is expressed in cardiovascular, renal, and central nervous systems, and its dysregulation is linked to hypertension, heart failure, and kidney injury [6,8].
• Both peptide and nonpeptide ligands have been developed as agonists and antagonists, providing pharmacological tools to probe receptor function [1,2,3,4].
• Recent evidence shows that remdesivir can activate UT, causing cardiomyocyte dysfunction, highlighting drug repurposing safety concerns.
• CRISPR-based knockout, knock-in, and overexpression models are essential to dissect UTS2R signaling in health and disease.
Description
Urotensin II receptor activity (GO:0001604) is the molecular function of binding the peptide hormone urotensin II (UII) and transmitting a signal that alters cellular behavior. This activity is mediated by the urotensin II receptor (UT), a G protein-coupled receptor (GPCR) encoded by the UTS2R gene, which is expressed in a wide range of tissues including the cardiovascular system, kidney, and brain [5,6]. The UII/UT axis is one of the most potent vasoactive systems known, and its dysregulation has been implicated in hypertension, heart failure, and renal injury [6,8]. Understanding the precise molecular mechanisms of UT activation is therefore critical for both basic physiology and therapeutic development. The receptor has attracted considerable attention as a drug target, with extensive efforts to develop peptide and nonpeptide agonists and antagonists [1,2,3,4]. More recently, the discovery that remdesivir can activate UT and induce cardiomyocyte dysfunction has underscored the need for careful pharmacological profiling of GPCR activity. This article provides a research-grade overview of GO:0001604, covering its definition, mechanism, key genes, disease relevance, and state-of-the-art methods for studying it.
urotensin II receptor activity At A Glance
| GO ID | GO:0001604 |
|---|---|
| GO term | urotensin II receptor activity |
| Ontology | molecular_function |
| Synonym | none |
| Major function | Binding urotensin II and initiating intracellular signaling, typically via Gq/11-mediated calcium release |
| Receptor family | Class A (rhodopsin-like) G protein-coupled receptor |
| Endogenous ligand | Urotensin II (UII), a cyclic undecapeptide |
| Coding gene | UTS2R (also known as GPR14) |
| Tissue distribution | Cardiovascular system, kidney, brain, and other tissues |
What Is GO:0001604?
According to the Gene Ontology, urotensin II receptor activity (GO:0001604) is defined as the function of combining with urotensin II to initiate a change in cell activity. In practice, this means the receptor specifically binds UII and, upon binding, undergoes conformational changes that activate intracellular signaling pathways, most commonly through heterotrimeric G proteins. This activity is distinct from simple ligand binding because it requires signal transduction, and it is measured experimentally by downstream responses such as calcium mobilization, inositol phosphate production, or reporter gene activation [5,7].
Why Is urotensin II receptor activity Important in Cell Biology?
Urotensin II receptor activity is critically important because the UII/UT system is one of the most potent vasoconstrictor pathways known, and its overactivation contributes to cardiovascular and renal pathologies [6,8]. Moreover, UT is a validated drug target, with numerous agonists and antagonists developed for therapeutic applications [1,2,3,4]. The recent finding that remdesivir can activate UT and cause cardiomyocyte dysfunction further highlights the clinical relevance of this receptor in drug safety. Thus, understanding GO:0001604 at the molecular level is essential for both physiology and translational medicine.
• Regulates vascular tone and cardiac contractility, with UII being one of the most potent vasoconstrictors.
• Implicated in hypertension, heart failure, and atherosclerosis through overactivation of UT.
• Mediates kidney injury and hyperglycemia in diabetic models, as shown by UTS2R loss-of-function studies.
• Serves as a target for peptide and nonpeptide antagonists with therapeutic potential [1,3,4].
• Can be activated by remdesivir, leading to cardiomyocyte dysfunction and highlighting drug repurposing risks.
• Expressed in the central nervous system, where it may modulate neuroendocrine and behavioral functions.
• Involved in inflammatory responses, acting as an inflammatory cytokine mediator.
• Provides a model GPCR for studying biased agonism and allosteric modulation [3,4].
• Genetic knockout of UTS2R in mice protects against streptozotocin-induced hyperglycemia and kidney injury.
• Offers opportunities for CRISPR-based disease modeling and drug discovery.
What Happens During urotensin II receptor activity?
Ligand binding and receptor activation
In simple terms: Urotensin II binds to the UT receptor like a key in a lock, causing the receptor to change shape.
Urotensin II (UII) is a cyclic peptide that binds with high affinity to the extracellular loops and transmembrane domain of the UT receptor. This binding induces conformational changes in the receptor, particularly in transmembrane helix 6, leading to the activation of heterotrimeric G proteins. The receptor can also be activated by nonpeptide agonists, which may stabilize distinct active conformations.
G protein coupling and second messenger generation
In simple terms: Once activated, the receptor turns on G proteins, which then produce messenger molecules inside the cell.
The UT receptor primarily couples to Gq/11, activating phospholipase C beta (PLCβ), which hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). IP3 triggers calcium release from the endoplasmic reticulum, while DAG activates protein kinase C (PKC). The receptor may also couple to Gi/o and G12/13, modulating additional pathways.
Downstream signaling cascades
In simple terms: The messengers activate many proteins that change how the cell behaves, such as making it contract or grow.
Elevated calcium and PKC activation lead to phosphorylation of downstream targets, including myosin light chain kinase, which promotes smooth muscle contraction. UT signaling also activates RhoA/Rho kinase, MAPK/ERK, and PI3K/Akt pathways, contributing to cell proliferation, migration, and hypertrophy [5,6]. These pathways are relevant to cardiovascular remodeling and inflammation.
Receptor desensitization and internalization
In simple terms: After signaling, the receptor is turned off and pulled inside the cell to stop the response.
Following activation, the UT receptor is phosphorylated by G protein-coupled receptor kinases (GRKs) and binds β-arrestins, leading to desensitization and internalization via clathrin-coated pits. This process regulates the duration and intensity of signaling and can also initiate G protein-independent signaling through β-arrestin.
Key Genes Involved in GO:0001604 urotensin II receptor activity
The following genes and proteins are central to urotensin II receptor activity and its signaling network.
| Gene | Major Role | Research Relevance |
|---|---|---|
| UTS2R | Encodes the urotensin II receptor (UT), a class A GPCR that binds UII and activates Gq/11 | Primary target for knockout, knock-in, and overexpression studies to dissect UII signaling |
| UTS2 | Encodes urotensin II, the endogenous peptide ligand for UT | Ligand knockout models to study UII-dependent physiology and pathology |
| GNAQ | Encodes Gαq, which couples UT to phospholipase Cβ | Knockout or point mutation to study Gq-mediated signaling |
| GNA11 | Encodes Gα11, a close homolog of Gαq that also couples to UT | Double knockout with GNAQ to fully ablate Gq/11 signaling |
| PLCB1 | Encodes phospholipase C beta 1, which generates IP3 and DAG downstream of Gq | Knockdown or knockout to block UT-mediated calcium release |
| ARRB1 | Encodes β-arrestin 1, which mediates receptor desensitization and internalization | Knockout to study biased signaling and receptor trafficking |
| ARRB2 | Encodes β-arrestin 2, which also regulates UT desensitization | Knockout models to dissect arrestin-dependent pathways |
| GRK2 | Encodes G protein-coupled receptor kinase 2, which phosphorylates activated UT | Overexpression or knockout to modulate receptor desensitization |
| GRK5 | Encodes GRK5, another kinase that can phosphorylate UT | Knockout to study GRK specificity |
| RHOA | Encodes RhoA, a small GTPase activated downstream of UT | Knockout or dominant-negative mutants to study cytoskeletal remodeling |
| ROCK1 | Encodes Rho kinase 1, an effector of RhoA | Knockout or pharmacological inhibition to block UT-mediated contraction |
| MAPK1 | Encodes ERK2, a kinase activated by UT signaling | Knockout or point mutation to study proliferation pathways |
| MAPK3 | Encodes ERK1, another MAPK activated by UT | Knockout models to dissect MAPK contribution |
| AKT1 | Encodes Akt1, a kinase in the PI3K/Akt pathway activated by UT | Knockout or overexpression to study survival signaling |
| EDN1 | Encodes endothelin-1, which interacts with UII in vascular tone regulation | Double knockout with UTS2R to study crosstalk |
| NOS3 | Encodes endothelial nitric oxide synthase, which counteracts UII-induced vasoconstriction | Knockout to study endothelial dysfunction |
| AGT | Encodes angiotensinogen, part of the renin-angiotensin system that interacts with UII | Knockout or transgenic models to study hypertension |
| TGFB1 | Encodes TGF-β1, a profibrotic factor induced by UII | Knockout to study fibrosis in heart and kidney |
How Is urotensin II receptor activity Regulated?
Urotensin II receptor activity is regulated at multiple levels. Receptor expression is modulated by transcriptional factors and cytokines, with inflammatory mediators such as TNF-α and IL-1β increasing UTS2R transcription. At the protein level, agonist-induced phosphorylation by GRKs and subsequent β-arrestin binding lead to desensitization and internalization, thereby terminating signaling. Additionally, allosteric modulators and biased agonists can fine-tune receptor activity, as demonstrated by nonpeptide ligands that selectively activate G protein or β-arrestin pathways [3,4]. The renin-angiotensin system and endothelin system also crosstalk with UII/UT signaling, contributing to complex regulation in cardiovascular tissues.
urotensin II receptor activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| UTS2R | Hypertension and heart failure | UTS2R knockout mice, cardiac-specific overexpression |
| UTS2R | Diabetic nephropathy | Streptozotocin-treated UTS2R knockout mice |
| UTS2 | Atherosclerosis | ApoE knockout mice with UTS2 overexpression |
| UTS2R | Drug-induced cardiotoxicity | Human induced pluripotent stem cell-derived cardiomyocytes with UTS2R knockout |
| UTS2R | Pulmonary hypertension | Monocrotaline-treated rats with UT antagonist |
Cardiovascular diseases
Overactivation of the UII/UT system is implicated in hypertension, heart failure, and atherosclerosis. UII is one of the most potent vasoconstrictors, and elevated plasma UII levels correlate with cardiovascular risk. In animal models, UT antagonists reduce blood pressure and attenuate cardiac remodeling [1,3]. The recent finding that remdesivir activates UT and causes cardiomyocyte dysfunction further links this receptor to drug-induced cardiotoxicity.
Renal injury and diabetes
UT signaling contributes to kidney injury and hyperglycemia. In streptozotocin-treated mice, loss of UTS2R diminished hyperglycemia and kidney injury, suggesting that UT blockade may be renoprotective in diabetes. These findings highlight the therapeutic potential of UT antagonists for diabetic nephropathy.
Inflammation and fibrosis
Urotensin II acts as an inflammatory cytokine, promoting chemotaxis and cytokine release in immune cells. It also induces profibrotic factors such as TGF-β1, contributing to tissue fibrosis in heart and kidney. Targeting UT may therefore have anti-inflammatory and antifibrotic benefits.
From urotensin II receptor activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does UTS2R mediate UII-induced vasoconstriction? | UTS2R knockout mice |
| What is the role of Gq/11 coupling in UT signaling? | GNAQ/GNA11 double knockout cells |
| Can a point mutation in UTS2R cause biased signaling? | CRISPR knock-in of UTS2R point mutants |
| How does UTS2R overexpression affect cardiac hypertrophy? | Cardiac-specific UTS2R transgenic mice |
| Does UTS2R knockout protect against diabetic kidney injury? | Streptozotocin-treated UTS2R knockout mice |
| Can remdesivir-induced cardiotoxicity be prevented by UTS2R knockout? | Human iPSC-derived cardiomyocytes with UTS2R knockout |
How to Study the urotensin II receptor activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Calcium mobilization assay | Intracellular calcium flux upon UT activation | Screening for UT agonists/antagonists |
| Luciferase reporter assay | Activation of downstream transcription factors (e.g., SRF, NFAT) | Functional characterization of UT variants |
| Radioligand binding | Ligand-receptor binding affinity | Pharmacological profiling of UT ligands |
| CRISPR knockout screen | Genes required for UT signaling | Discovery of novel regulators |
| RNA-seq | Transcriptional changes upon UT activation | Identifying UII-induced gene expression programs |
| Proteomics | Protein phosphorylation and interaction networks | Mapping UT signaling complexes |
| Immunofluorescence | Subcellular localization of UT | Studying receptor trafficking |
| Patch-clamp electrophysiology | Ion channel activity modulated by UT | Cardiomyocyte function |
Calcium mobilization assays
UT activation leads to IP3-mediated calcium release, which can be measured using fluorescent calcium indicators such as Fluo-4 or genetically encoded sensors like GCaMP [5,7]. These assays are widely used to screen for agonists and antagonists and to characterize receptor mutants.
Reporter gene assays
Downstream signaling pathways such as MAPK/ERK or serum response factor (SRF) can be monitored using luciferase reporter constructs. These assays enable high-throughput screening of compound libraries and functional characterization of UT variants.
Radioligand binding
Binding affinity of UII or synthetic ligands to UT can be quantified using radiolabeled ligands (e.g., 125I-UII) in membrane preparations or whole cells [1,2]. This method provides direct measurement of receptor-ligand interactions and is useful for pharmacological profiling.
CRISPR-based genetic screens
Genome-wide CRISPR knockout or activation screens can identify genes that modulate UT signaling or UII-induced phenotypes. Such screens have revealed novel regulators of GPCR signaling and potential drug targets.
How CRISPR Can Be Used to Study GO:0001604 urotensin II receptor activity
Knockout
CRISPR-Cas9 knockout of UTS2R in cell lines or animal models abolishes UII binding and downstream signaling, providing a clean background to study receptor function. For example, UTS2R knockout mice are protected from streptozotocin-induced hyperglycemia and kidney injury. In vitro, UTS2R knockout cardiomyocytes show reduced remdesivir-induced dysfunction.
Point Mutation
CRISPR-mediated point mutations can introduce specific amino acid substitutions in UTS2R to dissect receptor structure-function relationships, such as residues involved in ligand binding or G protein coupling. These models are valuable for understanding biased agonism and allosteric modulation.
Knock-in
Knock-in of tagged UTS2R (e.g., HA or GFP) allows real-time visualization of receptor trafficking and interaction with β-arrestins. Knock-in of human UTS2R into mouse models can humanize the receptor for drug testing.
Overexpression
Overexpression of UTS2R via CRISPR activation or lentiviral delivery can amplify UII signaling, useful for studying gain-of-function phenotypes such as cardiac hypertrophy. Overexpression models also facilitate high-throughput screening of antagonists.
How EDITGENE Supports urotensin II receptor activity Research
Researchers studying urotensin II receptor activity-related genes often need to determine whether a candidate gene is causally involved in receptor signaling, cardiovascular pathology, or drug response. EDITGENE provides a comprehensive suite of CRISPR-based services to accelerate this research, from gene knockout to precise point mutations and library screening.
Contact EDITGENE today to design your custom CRISPR model for urotensin II receptor activity research.
Frequently Asked Questions About urotensin II receptor activity
What is urotensin II receptor activity?
Urotensin II receptor activity (GO:0001604) is the molecular function of binding the peptide urotensin II and initiating intracellular signaling, primarily through the G protein-coupled receptor UT.
What genes are involved in urotensin II receptor activity?
The primary gene is UTS2R, which encodes the receptor. Other key genes include UTS2 (ligand), GNAQ/GNA11 (G proteins), and PLCB1 (effector).
What diseases are associated with urotensin II receptor activity?
Dysregulation of UT signaling is linked to hypertension, heart failure, diabetic kidney injury, and inflammation [6,8].
How can I study urotensin II receptor activity in the lab?
Common methods include calcium mobilization assays, radioligand binding, reporter gene assays, and CRISPR-based genetic screens [5,8].
What is the role of UTS2R in the cardiovascular system?
UTS2R mediates potent vasoconstriction and cardiac remodeling, contributing to hypertension and heart failure.
Can urotensin II receptor be targeted by drugs?
Yes, both peptide and nonpeptide agonists and antagonists have been developed, with several showing efficacy in preclinical models [1,3,4].
What is the connection between remdesivir and urotensin II receptor?
Remdesivir can activate UT, leading to cardiomyocyte dysfunction, which may explain some of its cardiotoxic effects.
How does urotensin II receptor signaling work?
UII binding activates Gq/11, which stimulates phospholipase C to produce IP3 and DAG, leading to calcium release and PKC activation.
What are the knockout models for UTS2R?
UTS2R knockout mice are available and have been used to show protection against diabetic kidney injury and hyperglycemia.
What CRISPR services are available for urotensin II receptor research?
EDITGENE offers knockout, point mutation, knock-in, overexpression, and CRISPR library screening services tailored to UTS2R and related genes.
Conclusion
Urotensin II receptor activity (GO:0001604) is a critical molecular function mediated by the UT receptor, with profound implications for cardiovascular, renal, and inflammatory diseases. The UII/UT axis represents a promising therapeutic target, and ongoing research continues to uncover its complex regulation and crosstalk with other signaling systems [5,6]. Advances in CRISPR-based models and pharmacological tools will further elucidate the precise mechanisms of UT signaling and facilitate the development of novel therapeutics.
References
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- 2. Carotenuto A et al.. 2004. Urotensin-II receptor peptide agonists.. Med Res Rev 24(5):577-88 PMID: 15224381
- 3. Wei X et al.. 2023. Urotensin II Receptor Modulation with 1,3,4-Benzotriazepin-2-one Tetrapeptide Mimics.. J Med Chem 66(20):14241-14262 PMID: 37800680
- 4. Lescot E et al.. 2008. Nonpeptide Urotensin-II receptor agonists and antagonists: review and structure-activity relationships.. Peptides 29(5):680-90 PMID: 18022732
- 5. Svistunov AA et al.. 2018. Urotensin II: Molecular Mechanisms of Biological Activity.. Curr Protein Pept Sci 19(9):924-934 PMID: 28875851
- 6. Sun SL et al.. 2019. Urotensin II: an inflammatory cytokine.. J Endocrinol 240(3):R107-R117 PMID: 30601760
- 7. Ogawa A et al.. 2023. Activation of the urotensin-II receptor by remdesivir induces cardiomyocyte dysfunction.. Commun Biol 6(1):511 PMID: 37173432
- 8. Peixoto-Neves D et al.. 2022. Loss of urotensin II receptor diminishes hyperglycemia and kidney injury in streptozotocin-treated mice.. J Mol Endocrinol 68(3):167-178 PMID: 35244607
