GO:0015143 urate transmembrane transporter activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0015143 (urate transmembrane transporter activity) describes the molecular function that moves the urate anion across a biological membrane, and its synonym is uric acid transmembrane transporter activity.
• Multiple structurally distinct proteins can carry out this activity, including the galectin-9-related urate transporter/channel UAT, the SLC17A1 (NPT1) Cl(-)-dependent urate exporter, and the monocarboxylate transporter SLC16A9/hMCT9.
• Urate transport is central to purine metabolism because urate is the end product of purine catabolism in humans and the main excretory product in uricotelic animals.
• Genetic variation in urate transporter genes and in urate-handling pathways is reproducibly associated with serum urate concentration and gout risk in genome-wide association and pathway analyses.
• Some bacterial urate-responsive regulators, such as MarR homologs with a urate-binding signature, use urate binding to control gene expression, showing that urate recognition is an evolutionarily conserved biochemical function.
• CRISPR knockout, point-mutation, knock-in and overexpression models allow researchers to test whether a candidate urate transporter gene is causally involved in urate flux, serum urate regulation and disease.
Description
GO:0015143, urate transmembrane transporter activity, is a molecular function term in the Gene Ontology that enables the transfer of urate from one side of a membrane to the other. Urate is the anion of uric acid, 2,6,8-trioxypurine, the end product of purine metabolism in certain mammals and the main excretory product in uricotelic animals. Because urate is a charged metabolite that cannot freely diffuse across lipid bilayers, dedicated transporter proteins are required to move it between intracellular and extracellular compartments, and the activity of these proteins directly influences urate homeostasis. Researchers study GO:0015143 because urate transport sits at the intersection of purine catabolism, renal and intestinal excretion, and human disease. Functional expression studies identified a human urate transporter/channel, hUAT, and provided molecular models of how this protein conducts urate. A separate Cl(-)-dependent urate exporter activity was assigned to the type 1 sodium-dependent phosphate transporter SLC17A1 (NPT1), showing that urate efflux can be coupled to other ion gradients. More recently, the monocarboxylate transporter SLC16A9/hMCT9 has been characterized with respect to single-nucleotide polymorphisms that may affect its transport behavior. At the population level, pathway analyses of genome-wide association studies have linked urate transport and purine metabolism pathways to serum uric acid concentrations and gout risk. This makes GO:0015143 a useful annotation anchor for interpreting genetic association signals, prioritizing candidate genes, and designing mechanistic experiments in cell and animal models. The term also connects to broader biology, because urate-binding proteins such as MarR homologs use urate recognition to regulate gene expression in bacteria, and galectin-9-related UAT activity illustrates sugar-regulated urate transport.
urate transmembrane transporter activity At A Glance
| GO ID | GO:0015143 |
|---|---|
| GO term | urate transmembrane transporter activity |
| Ontology | molecular_function |
| Synonym | uric acid transmembrane transporter activity |
| Major function | Transfer of the urate anion from one side of a membrane to the other |
| Substrate | Urate (the anion of uric acid, 2,6,8-trioxypurine) |
| Biological context | End product of purine metabolism in certain mammals and main excretory product in uricotelic animals |
| Representative proteins | UAT/galectin-9-related urate transporter/channel, SLC17A1 (NPT1), SLC16A9 (hMCT9) |
| Disease relevance | Serum urate concentration, gout risk and urate-handling pathway associations |
What Is GO:0015143?
In plain terms, GO:0015143 means the cell has a protein machine whose job is to carry urate across a membrane. The official Gene Ontology definition states that this activity enables the transfer of urate from one side of a membrane to the other, where urate is the anion of uric acid, 2,6,8-trioxypurine, the end product of purine metabolism in certain mammals and the main excretory product in uricotelic animals. The synonym uric acid transmembrane transporter activity is used interchangeably. Functionally, this is a transporter activity: it describes the movement of a specific small-molecule substrate, urate, across a lipid bilayer, rather than a signaling or catalytic activity. Experimentally, the activity is detected by measuring urate flux across membranes or by reconstituting candidate proteins and observing urate transport.
Why Is urate transmembrane transporter activity Important in Cell Biology?
GO:0015143 matters because urate is a terminal purine metabolite whose concentration in blood and tissues must be tightly controlled, and that control depends on transporter proteins that move urate across membranes. When urate transport activity is altered, urate can accumulate or be lost inappropriately, which is directly relevant to hyperuricemia and gout. Pathway analyses of genome-wide association studies have shown that urate transport and purine metabolism pathways influence serum urate levels and gout risk, making this GO term a practical annotation for interpreting genetic data. The activity is also mechanistically interesting because different proteins achieve urate movement using different coupling mechanisms, such as Cl(-)-dependent export by SLC17A1 and channel-like behavior by hUAT. Finally, urate recognition is not limited to transport: bacterial MarR homologs with a urate-binding signature use urate binding to regulate transcription, and UAT activity is sugar-regulated, showing that urate transport and sensing are integrated into broader cellular physiology.
• Defines the molecular function responsible for moving urate across membranes, a prerequisite for urate excretion and distribution.
• Links directly to purine metabolism, because urate is the end product of purine catabolism in certain mammals.
• Provides a mechanistic explanation for genetic associations between urate transporter genes and serum urate concentration.
• Supports gout research, since urate handling pathways are associated with gout risk in pathway-level analyses.
• Highlights SLC17A1 (NPT1) as a Cl(-)-dependent urate exporter, showing ion-coupled urate efflux.
• Highlights SLC16A9/hMCT9 as a monocarboxylate transporter whose polymorphisms have been characterized.
• Connects to channel-like urate transport by hUAT and its molecular models.
• Reveals sugar-regulated urate transport through galectin-9-related UAT.
• Shows evolutionary conservation of urate recognition through bacterial MarR homologs with a urate-binding signature.
• Offers a clear target for CRISPR-based causal testing of candidate urate transporter genes.
Molecular Mechanism of urate transmembrane transporter activity
Substrate recognition and binding of urate
In simple terms: First, the transporter must recognize and grab urate.
Urate transmembrane transporter activity begins with substrate recognition, in which the transporter protein binds the urate anion. Structural and functional work on the human urate transporter/channel hUAT produced molecular models of the protein and its functional behavior, supporting a defined urate-binding and conduction pathway. In bacteria, MarR homologs carry a urate-binding signature, demonstrating that proteins can evolve specific urate-recognition pockets that discriminate urate from related metabolites. This step is the basis for substrate specificity of GO:0015143.
Membrane translocation of urate
In simple terms: Next, the protein carries urate across the membrane.
After binding, the transporter moves urate from one side of the membrane to the other. Functional analysis of the cloned urate transporter/channel established that the protein can conduct urate across membranes, and molecular modeling suggested a channel-like route for urate movement. The human urate transporter/channel hUAT was similarly analyzed functionally and modeled, supporting a membrane translocation step for urate. This translocation is the defining event of GO:0015143.
Ion-coupled urate export by SLC17A1 (NPT1)
In simple terms: Some transporters use chloride as a partner to push urate out.
The type 1 sodium-dependent phosphate transporter SLC17A1 (NPT1) functions as a Cl(-)-dependent urate exporter, meaning urate efflux is coupled to chloride. This shows that urate transmembrane transporter activity can be energetically and mechanistically linked to the movement of another ion, rather than being a simple pore. This coupling expands the mechanistic repertoire of GO:0015143 and provides a distinct experimental signature for urate export assays.
Regulation by sugars and galectin-9-related UAT
In simple terms: Urate transport can be tuned by sugar signals.
Galectin 9 is a sugar-regulated urate transporter/channel known as UAT, indicating that urate transport activity can be modulated by sugar-binding status. This links GO:0015143 to carbohydrate recognition biology and suggests that urate flux is not constitutive but can be regulated. Such regulation may be relevant when interpreting urate transport in metabolic contexts where sugar availability changes.
Genetic variation in SLC16A9/hMCT9 and transport behavior
In simple terms: Small DNA changes in a transporter gene can alter how it works.
SLC16A9/hMCT9 is a monocarboxylate transporter, and single-nucleotide polymorphisms in SLC16A9/hMCT9 have been analyzed at the molecular level. Because urate transport pathways are associated with serum urate concentration, characterizing how polymorphisms affect transporter behavior is a direct way to connect genotype to urate transmembrane transporter activity. This subsection emphasizes that GO:0015143 can be tuned by naturally occurring sequence variants.
Key Genes Involved in GO:0015143 urate transmembrane transporter activity
The following genes and proteins have been experimentally or analytically linked to urate transmembrane transporter activity (GO:0015143) or to urate-handling pathways.
| Gene | Major Role | Research Relevance |
|---|---|---|
| UAT (galectin-9-related urate transporter/channel) | Sugar-regulated urate transporter/channel activity | Provides evidence that urate transport can be regulated by sugar status |
| SLC16A9 (hMCT9) | Monocarboxylate transporter with characterized SNPs | Links sequence variants to transporter molecular characteristics |
| MarR homologs (bacterial urate-binding regulators) | Urate-binding signature in transcriptional regulators | Shows conserved urate recognition outside transport |
| SLC17A1 (NPT1) | Cl(-)-dependent urate exporter | Demonstrates ion-coupled urate efflux |
| hUAT | Human urate transporter/channel | Functional analysis and molecular model of urate conduction |
| Urate transport pathway genes (GWAS pathway analysis) | Collective urate handling | Pathway analysis links urate transport to serum uric acid concentrations |
| Purine metabolism and urate transport pathway genes | Serum urate regulation and gout risk | Systematic pathway analysis links two pathways to serum urate and gout |
| Cloned urate transporter/channel | Functional urate transport and molecular modeling | Established channel-like urate conduction |
| SLC22A12 (URAT1) | Renal urate reabsorption transporter | Frequently studied in urate transport research; urate transport pathway member |
| SLC2A9 (GLUT9) | Urate transporter in kidney and intestine | Urate transport pathway gene implicated in serum urate regulation |
| ABCG2 | Urate efflux transporter | Urate transport pathway gene associated with gout risk |
| SLC17A3 | Urate exporter in kidney | Related to SLC17A1 urate export biology |
| SLC22A11 (OAT4) | Organic anion transporter with urate handling | Urate transport pathway candidate |
| SLC22A13 (OAT10) | Urate transporter | Urate transport pathway candidate |
| PDZK1 | Scaffold protein for urate transporters | Urate transport pathway component |
| GCKR | Metabolic regulator linked to urate | Urate pathway association in GWAS analyses |
| HNF1A | Transcription factor linked to urate | Urate pathway association in GWAS analyses |
| SLC16A9 | Monocarboxylate transporter | SNP characterization relevant to urate transport |
How Is urate transmembrane transporter activity Regulated?
Urate transmembrane transporter activity is regulated at multiple levels. At the protein level, UAT is sugar-regulated, meaning its urate transport/channel activity responds to sugar-binding status through its galectin-9-related nature. At the genetic level, single-nucleotide polymorphisms in SLC16A9/hMCT9 alter the molecular characteristics of the transporter, and common variation in urate transport pathway genes influences serum urate concentration. At the pathway level, systematic pathway analyses indicate that urate transport and purine metabolism pathways jointly influence serum urate levels and gout risk, implying coordinated regulation across multiple transporters rather than a single rate-limiting step. In bacteria, urate binding by MarR homologs regulates transcription, showing that urate itself can act as a regulatory signal. Together, these findings indicate that GO:0015143 is regulated by substrate availability, sugar signals, genetic variation and pathway-level coordination.
urate transmembrane transporter activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| SLC17A1 (NPT1) | Urate export and serum urate regulation | Knockout and Cl(-)-dependent urate efflux assays in renal epithelial cells |
| hUAT | Urate transport/channel activity linked to urate balance | Overexpression and patch/uptake assays in mammalian cells |
| SLC16A9 (hMCT9) | Monocarboxylate transport with SNP effects | Point-mutation knock-in of SNPs followed by transport assays |
| UAT (galectin-9-related) | Sugar-regulated urate transport | Knockout with sugar-conditioned urate flux measurements |
| Urate transport pathway genes | Serum urate concentration and gout risk | CRISPR library screening and pathway-level perturbation |
Hyperuricemia and gout
Urate transmembrane transporter activity directly determines how much urate is retained or excreted. Pathway analyses of genome-wide association studies have shown that urate transport and purine metabolism pathways influence serum urate levels and gout risk. Because SLC17A1 (NPT1) acts as a Cl(-)-dependent urate exporter and hUAT functions as a urate transporter/channel, altered activity of these proteins can shift urate balance. Genetic variants in urate transport genes are therefore plausible contributors to hyperuricemia and gout, and pathway-level evidence supports this link.
Metabolic and sugar-related conditions
UAT is a sugar-regulated urate transporter/channel related to galectin 9, which raises the possibility that urate transport activity is altered in metabolic states characterized by changes in sugar availability. SLC16A9/hMCT9 is a monocarboxylate transporter whose polymorphisms have been characterized, further connecting urate transport biology to metabolic transport systems. These observations suggest that urate transmembrane transporter activity may be a mechanistic node linking sugar and monocarboxylate metabolism to urate homeostasis.
Microbial urate sensing and host-microbe interactions
MarR homologs with a urate-binding signature use urate recognition to regulate gene expression in bacteria. This indicates that urate is not only a transport substrate but also a regulatory molecule in microbial systems. Because urate is the main excretory product in uricotelic animals and an end product of purine metabolism in certain mammals, microbial urate sensing may influence host-microbe interactions in urate-rich environments, although direct clinical evidence remains to be established.
From urate transmembrane transporter activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is a candidate gene required for urate transport? | CRISPR knockout in a urate-transporting cell line followed by urate flux assay |
| Does a specific SNP alter transporter function? | Point-mutation knock-in of the SNP in the endogenous locus |
| Does adding a tag change localization or activity? | Tagged knock-in of the transporter gene |
| Does increased dosage of the transporter change urate handling? | Overexpression of the transporter in a relevant cell model |
| Which pathways control urate transport? | CRISPR library screening combined with urate readouts |
| How does sugar status affect urate transport? | Knockout or overexpression of UAT under controlled sugar conditions |
How to Study the urate transmembrane transporter activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Urate flux assay | Movement of urate across membranes | Assigning GO:0015143 to a candidate gene |
| Cl(-)-dependent export assay | Urate efflux coupled to chloride | Characterizing SLC17A1 (NPT1) activity |
| Molecular modeling | Predicted urate binding and conduction pathway | Interpreting hUAT and cloned transporter function |
| SNP functional characterization | Effect of sequence variants on transporter behavior | Analyzing SLC16A9/hMCT9 polymorphisms |
| GWAS pathway analysis | Enrichment of urate transport pathways in association signals | Linking pathways to serum urate and gout |
| Sugar-regulated transport assay | Urate transport as a function of sugar status | Studying UAT regulation |
| Urate-binding signature analysis | Presence of urate-binding motifs | Identifying MarR homologs |
| CRISPR knockout transport screen | Requirement of genes for urate transport | Causal testing of candidate urate transporters |
Urate flux and uptake assays
Direct measurement of urate transmembrane transporter activity relies on flux or uptake assays in cells expressing the candidate transporter. Functional analysis of the cloned urate transporter/channel and hUAT used such approaches to demonstrate urate conduction and to support molecular models. Cl(-)-dependent urate export by SLC17A1 (NPT1) was likewise established through transport assays. These methods remain the gold standard for assigning GO:0015143 to a gene product.
Molecular modeling and structure-function analysis
Molecular models of hUAT and the cloned urate transporter/channel have been used to propose urate conduction pathways and to interpret functional data. Such modeling helps generate hypotheses about substrate binding and translocation that can be tested by mutagenesis. Combined with SNP characterization in SLC16A9/hMCT9, structure-function analysis connects sequence variation to transport behavior.
Genetic association and pathway analysis
Pathway analysis of genome-wide association studies has been used to link urate transport and purine metabolism pathways to serum uric acid concentrations and gout risk. These computational methods identify which transporter genes and pathways are enriched for disease-associated variants, providing a prioritized list for experimental follow-up. They are essential for translating population genetics into mechanistic hypotheses about GO:0015143.
Microbial and comparative urate-binding studies
MarR homologs with a urate-binding signature have been identified through protein sequence and structural analysis, revealing conserved urate recognition. Comparative studies of such regulators can inform how urate-binding pockets are organized. Together with sugar-regulated UAT, these approaches broaden the study of urate recognition beyond human transporters.
How CRISPR Can Be Used to Study GO:0015143 urate transmembrane transporter activity
Knockout
CRISPR knockout of a candidate urate transporter gene removes the protein and allows direct testing of whether urate transmembrane transporter activity depends on it. For example, knocking out SLC17A1 (NPT1) or hUAT orthologs in a urate-transporting cell line followed by urate flux assays can establish causality. Knockout models are also useful for pathway-level questions raised by GWAS pathway analyses.
Point Mutation
Point-mutation knock-in introduces a specific nucleotide change, such as a SNP identified in SLC16A9/hMCT9, into the endogenous locus. This preserves physiological expression levels and allows precise measurement of how a single variant alters urate transport activity. Point-mutation models are ideal for linking genetic association signals in urate transport pathways to molecular function.
Knock-in
Knock-in strategies can add epitope tags, fluorescent reporters or regulatory elements to endogenous urate transporter genes. Tagged knock-in enables localization and interaction studies of proteins such as hUAT or SLC17A1 (NPT1) without overexpression artifacts. Knock-in of reporter cassettes can also be used to monitor transporter gene expression in response to sugar or metabolic signals.
Overexpression
Overexpression of a urate transporter gene increases protein levels and can amplify transport signals for biochemical assays. This approach was conceptually used in functional studies of hUAT and the cloned urate transporter/channel, and it remains useful for testing whether increased dosage of a transporter changes urate handling. Overexpression complements knockout and point-mutation models by revealing gain-of-function effects.
How EDITGENE Supports urate transmembrane transporter activity Research
Researchers studying urate transmembrane transporter activity-related genes often need to determine whether a candidate gene is causally involved in urate flux, serum urate regulation or disease risk. Functional assays alone can suggest an association, but CRISPR-based perturbation provides the causal evidence required for publication-grade conclusions. EDITGENE provides the cell models and screening services needed to move from candidate gene to validated mechanism.
Contact EDITGENE today to design your custom CRISPR model for urate transmembrane transporter activity research.
Frequently Asked Questions About urate transmembrane transporter activity
What is GO:0015143?
GO:0015143 is the Gene Ontology molecular function term urate transmembrane transporter activity, which enables the transfer of urate from one side of a membrane to the other.
What is urate transmembrane transporter activity?
It is the activity of a protein that moves the urate anion across a biological membrane, also known as uric acid transmembrane transporter activity.
What genes are involved in urate transmembrane transporter activity?
Genes and proteins linked to this activity include UAT (galectin-9-related), SLC16A9/hMCT9, SLC17A1 (NPT1) and hUAT, among others.
How is urate transported across membranes?
Urate is transported by dedicated proteins such as hUAT, which functions as a urate transporter/channel, and by SLC17A1 (NPT1), which acts as a Cl(-)-dependent urate exporter.
Why is urate transport important for gout?
Pathway analyses of genome-wide association studies show that urate transport and purine metabolism pathways influence serum urate levels and gout risk.
Is urate transport regulated by sugars?
Yes, UAT is a sugar-regulated urate transporter/channel related to galectin 9, indicating that sugar status can modulate urate transport.
What is the role of SLC17A1 in urate transport?
SLC17A1 (NPT1) functions as a Cl(-)-dependent urate exporter, coupling urate efflux to chloride.
What is the role of SLC16A9 in urate transport?
SLC16A9/hMCT9 is a monocarboxylate transporter whose single-nucleotide polymorphisms have been characterized at the molecular level, linking sequence variation to transporter behavior.
Do bacteria have urate-binding proteins?
Yes, MarR homologs with a urate-binding signature have been identified, showing that urate recognition is conserved beyond transport.
How can CRISPR help study urate transporters?
CRISPR knockout, point-mutation, knock-in and overexpression models allow causal testing of whether a candidate gene is required for urate transmembrane transporter activity.
Conclusion
GO:0015143, urate transmembrane transporter activity, defines the molecular function that moves the urate anion across membranes, a process essential for purine metabolism and urate excretion. The activity is carried out by structurally diverse proteins, including the sugar-regulated UAT, the Cl(-)-dependent exporter SLC17A1 (NPT1), the monocarboxylate transporter SLC16A9/hMCT9 and the human urate transporter/channel hUAT. Genetic and pathway evidence links urate transport to serum urate concentration and gout risk, and conserved urate recognition is observed even in bacterial regulators. For researchers, GO:0015143 provides a precise annotation to guide mechanistic experiments. CRISPR-based knockout, point-mutation, knock-in and overexpression models, combined with urate flux assays and pathway analysis, offer a rigorous route from candidate gene to causal mechanism. EDITGENE supports this workflow with custom cell models, library screening and bioinformatics services tailored to urate transporter research.
References
- 1. Lipkowitz MS et al.. 2002. Galectin 9 is the sugar-regulated urate transporter/channel UAT.. Glycoconj J 19(7-9):491-8 PMID: 14758072
- 2. Yamaguchi A et al.. 2023. Molecular characteristic analysis of single-nucleotide polymorphisms in SLC16A9/hMCT9.. Life Sci 334:122205 PMID: 37879602
- 3. Perera IC et al.. 2011. MarR homologs with urate-binding signature.. Protein Sci 20(3):621-9 PMID: 21432936
- 4. Iharada M et al.. 2010. Type 1 sodium-dependent phosphate transporter (SLC17A1 Protein) is a Cl(-)-dependent urate exporter.. J Biol Chem 285(34):26107-13 PMID: 20566650
- 5. Leal-Pinto E et al.. 2002. Functional analysis and molecular model of the human urate transporter/channel, hUAT.. Am J Physiol Renal Physiol 283(1):F150-63 PMID: 12060597
- 6. Lee YH et al.. 2012. Pathway analysis of genome-wide association studies on uric acid concentrations.. Hum Immunol 73(8):805-10 PMID: 22609445
- 7. Dong Z et al.. 2018. Genetic variants in two pathways influence serum urate levels and gout risk: a systematic pathway analysis.. Sci Rep 8(1):3848 PMID: 29497127
- 8. Leal-Pinto E et al.. 1999. Functional analysis and molecular modeling of a cloned urate transporter/channel.. J Membr Biol 169(1):13-27 PMID: 10227848
