GO:0042017 interleukin-22 binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0042017 (interleukin-22 binding) is a molecular function defined as binding to interleukin-22 (IL-22), the cytokine ligand of the IL-22 receptor complex.
• IL-22 binding is mediated by the heterodimeric receptor IL-22R1 (IL22RA1) and IL-10R2 (IL10RB), which together transduce IL-22 signals in epithelial and stromal cells.
• The soluble decoy IL-22 binding protein (IL-22BP, encoded by IL22RA2) competes with membrane IL-22R1 for IL-22 binding and modulates IL-22 bioavailability.
• IL-22 binding and signaling are central to mucosal immunity, Paneth cell formation, gut barrier function, and the gut microbiota-bile acid-IL-22 axis.
• Dysregulated IL-22 binding is implicated in polycystic ovary syndrome, psoriasis, metabolic disorders, trauma outcomes, and cancer metastasis.
• CRISPR-based knockout, knock-in, point-mutation, and overexpression models enable causal dissection of IL-22 binding in disease-relevant cell types.
Description
Interleukin-22 binding (GO:0042017) is the molecular function by which a protein or protein complex selectively recognizes and binds the cytokine interleukin-22 (IL-22). IL-22 is a member of the IL-10 cytokine family and acts primarily on non-hematopoietic cells such as epithelial cells, where it regulates proliferation, antimicrobial peptide production, and tissue repair. The canonical IL-22 binding event occurs at the cell surface through the heterodimeric receptor composed of IL-22R1 (IL22RA1) and IL-10R2 (IL10RB), and it is also modulated by the soluble decoy receptor IL-22 binding protein (IL-22BP, IL22RA2). Because IL-22 binding sits at the interface between immune signaling and epithelial barrier function, it is a high-value target for researchers studying mucosal immunity, metabolic disease, and cancer. Understanding the precise molecular determinants of IL-22 binding enables rational design of CRISPR models, therapeutic antibodies, and receptor agonists or antagonists.
interleukin-22 binding At A Glance
| GO ID | GO:0042017 |
|---|---|
| GO term | interleukin-22 binding |
| Ontology | molecular_function |
| Synonym | IL-22 binding |
| Definition | Binding to interleukin-22. |
| Major function | Mediates recognition of IL-22 by the IL-22 receptor complex and the soluble decoy IL-22BP, initiating or modulating downstream signaling. |
| Key receptor subunits | IL22RA1 (IL-22R1) and IL10RB (IL-10R2) form the functional IL-22 receptor complex. |
| Endogenous modulator | IL22RA2 (IL-22BP) is a soluble decoy that binds IL-22 and prevents receptor activation. |
| Primary cell types | Epithelial cells, keratinocytes, hepatocytes, and stromal cells that express IL-22R1. |
| Associated diseases | Polycystic ovary syndrome, psoriasis, metabolic disorders, trauma, and cancer metastasis. |
What Is GO:0042017?
According to the Gene Ontology, GO:0042017 (interleukin-22 binding) is defined as the molecular function of binding to interleukin-22. In practical terms, it describes any protein or protein complex that physically interacts with IL-22, including the membrane receptor IL-22R1 and the soluble decoy IL-22BP. This binding event is the first step in IL-22 signal transduction and determines whether IL-22 is available to activate downstream JAK-STAT signaling in target cells.
Why Is interleukin-22 binding Important in Cell Biology?
IL-22 binding is important because it determines the bioavailability and cellular specificity of IL-22, a cytokine that sits at the crossroads of immunity, metabolism, and tissue repair. The balance between membrane IL-22R1 binding and soluble IL-22BP sequestration controls whether IL-22 drives protective epithelial regeneration or contributes to pathological inflammation and tumor progression. Consequently, GO:0042017 is a focal point for understanding diseases as diverse as polycystic ovary syndrome, psoriasis, diet-induced metabolic disorders, and cancer metastasis.
• IL-22 binding initiates JAK-STAT signaling that drives antimicrobial peptide production and epithelial regeneration.
• The IL-22/IL-22BP axis is dysregulated in polycystic ovary syndrome and correlates with oral contraceptive use.
• IL-22 binding on keratinocytes contributes to psoriatic skin inflammation through autophagy-based HMGB1 secretion.
• Down-regulating the IL-22/IL-22BP axis promotes inflammation and aggravates diet-induced metabolic disorders.
• T cell-derived IL-22 binding to cancer cells induces CD155 and suppresses NK cell function, promoting metastasis.
• IL-22 and IL-22BP signaling influence intubation status in trauma patients, highlighting clinical relevance.
• IL-22 binding is required for Paneth cell formation in human intestinal organoids.
• The gut microbiota-bile acid-IL-22 axis links microbial metabolism to host immune regulation.
• IL-22 binding influences the Th1/Th17 axis, connecting innate and adaptive immunity.
• CRISPR models of IL22RA1, IL10RB, and IL22RA2 enable causal testing of IL-22 binding in disease.
Molecular Mechanism of interleukin-22 binding
Ligand recognition by IL-22R1
In simple terms: IL-22 first docks onto a specific receptor subunit called IL-22R1.
IL-22 binding begins when the cytokine engages the extracellular domain of IL-22R1 (IL22RA1), the ligand-specific subunit of the IL-22 receptor complex. This interaction is the primary determinant of cellular responsiveness to IL-22, because IL-22R1 expression is restricted largely to epithelial and stromal cells. Structural and functional studies indicate that IL-22R1 provides the high-affinity binding site for IL-22, while the second subunit, IL-10R2, is shared with other IL-10 family cytokines.
Assembly of the IL-22R1/IL-10R2 heterodimer
In simple terms: After IL-22 binds IL-22R1, a second receptor subunit joins to form the active signaling complex.
Following initial IL-22 binding to IL-22R1, the ubiquitously expressed IL-10R2 (IL10RB) subunit is recruited to form the heterodimeric receptor complex. This assembly is required for productive signal transduction, because neither subunit alone can fully activate downstream JAK-STAT pathways. The heterodimer then triggers phosphorylation of JAK kinases and STAT molecules, leading to expression of IL-22 target genes such as antimicrobial peptides and mucins.
Competition by the soluble decoy IL-22BP
In simple terms: A soluble protein called IL-22BP can capture IL-22 before it reaches the cell surface receptor.
IL-22 binding protein (IL-22BP, encoded by IL22RA2) is a soluble decoy receptor that binds IL-22 with high affinity and prevents it from engaging membrane IL-22R1. By sequestering IL-22, IL-22BP reduces the effective concentration of free cytokine and dampens IL-22 signaling in target tissues. The balance between IL-22R1 and IL-22BP expression therefore acts as a rheostat that tunes IL-22 activity in health and disease.
Downstream signaling and functional outcomes
In simple terms: Once IL-22 is bound, the receptor sends signals that change gene expression in the target cell.
IL-22 binding to the IL-22R1/IL-10R2 complex activates JAK1, TYK2, and STAT3, which translocate to the nucleus and drive transcription of genes involved in epithelial barrier function, antimicrobial defense, and tissue repair. In intestinal organoids, IL-22 binding is required for Paneth cell formation, demonstrating a direct link between this molecular function and epithelial differentiation. In cancer cells, IL-22 binding induces CD155 expression, which suppresses NK cell function and promotes metastasis.
Regulation by the microbiota-bile acid axis
In simple terms: Gut microbes and bile acids can change how much IL-22 is available to bind its receptor.
The gut microbiota-bile acid-IL-22 axis regulates IL-22 production and bioavailability, thereby influencing IL-22 binding to its receptor in the intestine. Bile acids modulated by the microbiota can affect IL-22 secretion from immune cells, which in turn determines the extent of IL-22R1 engagement on epithelial cells. This axis has been linked to polycystic ovary syndrome, where IL-22 binding and signaling are altered.
Key Genes Involved in GO:0042017 interleukin-22 binding
The following genes encode the ligands, receptors, decoy proteins, and signaling components that directly participate in or regulate interleukin-22 binding (GO:0042017).
| Gene | Major Role | Research Relevance |
|---|---|---|
| IL22 | Cytokine ligand that binds IL-22R1 and IL-22BP | Central ligand for GO:0042017; produced by T cells, NK cells, and innate lymphoid cells |
| IL22RA1 | Ligand-specific subunit of the IL-22 receptor complex | Primary membrane receptor mediating IL-22 binding and signaling |
| IL10RB | Shared subunit that completes the IL-22 receptor heterodimer | Required for productive IL-22 signal transduction |
| IL22RA2 | Soluble decoy receptor (IL-22BP) that sequesters IL-22 | Modulates IL-22 bioavailability and is dysregulated in PCOS and metabolic disease |
| JAK1 | Kinase activated downstream of IL-22 binding | Mediates STAT phosphorylation following receptor engagement |
| TYK2 | Kinase associated with IL-10R2 in the IL-22 receptor complex | Contributes to IL-22 signal transduction |
| STAT3 | Transcription factor activated by IL-22 binding | Drives expression of IL-22 target genes in epithelial cells |
| STAT1 | Transcription factor activated by IL-22 in some contexts | Modulates IL-22-dependent gene expression |
| HMGB1 | Nuclear protein secreted by keratinocytes during psoriatic inflammation | Links IL-22 binding to autophagy-based inflammation in psoriasis |
| CD155 (PVR) | Immune checkpoint ligand induced by IL-22 in cancer cells | Mediates NK cell suppression and metastasis downstream of IL-22 binding |
| MUC1 | Mucin gene induced by IL-22 signaling | Readout of IL-22 receptor activation in epithelial cells |
| REG3A | Antimicrobial peptide induced by IL-22 | Functional marker of IL-22 binding and STAT3 activation |
| REG3G | Antimicrobial peptide induced by IL-22 | Marker of IL-22-dependent epithelial defense |
| LYZ | Lysozyme expressed in Paneth cells | Paneth cell marker dependent on IL-22 binding in organoids |
| DEFA5 | Defensin expressed in Paneth cells | Paneth cell marker dependent on IL-22 binding |
| IL17A | Th17 cytokine influenced by IL-22 signaling | Connects IL-22 binding to Th1/Th17 balance |
| IFNG | Th1 cytokine influenced by IL-22 signaling | Connects IL-22 binding to Th1/Th17 balance |
| CYP7B1 | Bile acid synthesis enzyme in the microbiota-bile acid-IL-22 axis | Links bile acid metabolism to IL-22 binding in PCOS |
How Is interleukin-22 binding Regulated?
IL-22 binding is regulated at multiple levels. The expression of IL22RA1 determines which cells can bind IL-22, while IL22RA2 (IL-22BP) acts as a soluble decoy that sequesters IL-22 and prevents receptor engagement. The gut microbiota-bile acid axis modulates IL-22 production and bioavailability, thereby indirectly regulating IL-22 binding in the intestine. In addition, IL-22 signaling influences the Th1/Th17 axis, creating feedback that can shape IL-22 availability and receptor engagement. Down-regulation of the IL-22/IL-22BP axis promotes inflammation and aggravates diet-induced metabolic disorders, indicating that the balance of these regulators is critical for metabolic homeostasis.
interleukin-22 binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| IL22 | Polycystic ovary syndrome, metabolic disorders | Il22 knockout mouse; diet-induced obesity model |
| IL22RA1 | Psoriasis, cancer metastasis | Keratinocyte-specific Il22ra1 knockout; tumor xenograft |
| IL22RA2 | PCOS, trauma, metabolic disorders | Il22ra2 knockout mouse; trauma model |
| IL10RB | IL-22 signaling deficiency | Il10rb knockout organoids; epithelial cells |
| STAT3 | Epithelial barrier dysfunction | Stat3 conditional knockout in intestinal epithelium |
Polycystic ovary syndrome and metabolic disorders
The gut microbiota-bile acid-IL-22 axis is altered in polycystic ovary syndrome, where changes in IL-22 binding and signaling contribute to metabolic and reproductive dysfunction. The IL-22/IL-22BP axis is also associated with oral contraceptive use in PCOS, suggesting that hormonal status influences IL-22 bioavailability. In diet-induced metabolic disorders, down-regulating the IL-22/IL-22BP axis promotes inflammation and aggravates disease, highlighting the protective role of IL-22 binding.
Psoriasis and skin inflammation
IL-22 binding to keratinocytes contributes to psoriatic skin inflammation through autophagy-based unconventional secretion of HMGB1. This pathway links IL-22 receptor engagement to the release of a pro-inflammatory alarmin, amplifying skin inflammation. Targeting IL-22 binding or downstream signaling may therefore be therapeutically relevant in psoriasis.
Cancer metastasis and immune evasion
T cell-derived IL-22 binds to cancer cells and drives expression of CD155, which suppresses NK cell function and promotes metastasis. This demonstrates that IL-22 binding can directly remodel the tumor microenvironment to favor immune evasion. Blocking IL-22 binding or CD155 induction may represent a strategy to restore NK cell-mediated tumor control.
Trauma and critical illness
The IL-22 and IL-22BP signaling axis influences intubation status in trauma patients, indicating that IL-22 binding is clinically relevant in acute injury. Measuring IL-22 and IL-22BP levels may help stratify trauma patients at risk of respiratory failure. This underscores the importance of IL-22 binding beyond chronic inflammatory diseases.
From interleukin-22 binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does IL22RA1 mediate IL-22 binding in epithelial cells? | IL22RA1 knockout cell line or organoid |
| Does IL-22BP sequester IL-22 and modulate signaling? | IL22RA2 overexpression or knockout model |
| Which residues of IL-22 are required for receptor binding? | Point-mutation knock-in of IL22 |
| Can tagged IL-22R1 track receptor localization? | Knock-in of fluorescent or epitope tag at IL22RA1 locus |
| Does IL-22 binding drive Paneth cell formation? | Human intestinal organoid with IL22RA1 knockout |
| Does IL-22 binding induce CD155 in cancer cells? | Cancer cell line with IL22RA1 knockout or overexpression |
How to Study the interleukin-22 binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| CRISPR knockout | Loss of gene function | Test requirement for IL22RA1, IL10RB, or IL22RA2 in IL-22 binding |
| Knock-in tagging | Protein localization and dynamics | Track IL-22R1 or IL-22BP in live cells |
| RNA-seq | Transcriptional changes | Identify IL-22 target genes after receptor binding |
| ELISA | IL-22 and IL-22BP protein levels | Measure ligand and decoy in patient samples |
| Surface plasmon resonance | Binding affinity | Quantify IL-22-IL-22R1 interaction |
| Organoid culture | Epithelial differentiation | Assess Paneth cell formation dependent on IL-22 binding |
| Phospho-STAT3 immunoblot | Receptor signaling activation | Confirm functional IL-22 binding |
| Co-immunoprecipitation | Protein-protein interaction | Detect IL-22-IL-22BP complexes |
CRISPR knockout and knock-in models
CRISPR-Cas9 knockout of IL22RA1, IL10RB, or IL22RA2 allows researchers to test whether IL-22 binding is required for specific cellular responses. Knock-in of tagged or mutant alleles enables precise tracking of receptor localization and binding dynamics. These models are essential for causal inference in IL-22 biology.
Organoid and epithelial cell assays
Human intestinal organoids have been used to demonstrate that IL-22 binding is required for Paneth cell formation, providing a physiologically relevant model for studying GO:0042017. Organoids can be combined with CRISPR knockout to dissect receptor requirements. Epithelial cell lines are also widely used for IL-22 stimulation and STAT3 phosphorylation assays.
Transcriptomics and target gene readouts
RNA sequencing after IL-22 stimulation reveals the transcriptional program downstream of IL-22 binding, including antimicrobial peptides and mucins. Quantitative PCR for REG3A, REG3G, MUC1, and DEFA5 provides rapid readouts of IL-22 receptor activation. These methods link molecular binding events to functional outcomes.
Protein interaction and binding assays
Surface plasmon resonance, ELISA, and co-immunoprecipitation can measure direct binding between IL-22 and IL-22R1 or IL-22BP. These assays quantify affinity and competition between membrane receptor and soluble decoy. They are critical for validating GO:0042017 annotations.
How CRISPR Can Be Used to Study GO:0042017 interleukin-22 binding
Knockout
CRISPR knockout of IL22RA1, IL10RB, or IL22RA2 is used to determine whether IL-22 binding is required for downstream signaling and cellular responses. For example, IL22RA1 knockout organoids fail to form Paneth cells in response to IL-22, demonstrating an essential role for receptor binding. Knockout of IL22RA2 increases free IL-22 and enhances signaling, confirming its decoy function.
Point Mutation
Point mutations in IL22 or IL22RA1 can be introduced to map the residues required for high-affinity binding. Such models help distinguish binding-deficient from signaling-deficient alleles. They are valuable for validating structural predictions and for engineering receptor variants.
Knock-in
Knock-in of fluorescent or epitope tags at the IL22RA1 or IL22RA2 loci enables real-time tracking of receptor and decoy localization. Tagged knock-in models can also be used to pull down binding partners and quantify receptor turnover. These models are compatible with organoid and in vivo studies.
Overexpression
Overexpression of IL22, IL22RA1, or IL22RA2 in cell lines is used to amplify IL-22 binding and signaling for biochemical assays. Overexpression of IL22RA2 suppresses IL-22 signaling by sequestering the ligand, confirming its decoy role. Overexpression of IL-22 in cancer cells induces CD155 and promotes NK cell suppression.
How EDITGENE Supports interleukin-22 binding Research
Researchers studying interleukin-22 binding-related genes often need to determine whether a candidate gene is causally involved in ligand recognition, receptor assembly, or downstream signaling. EDITGENE provides publication-ready CRISPR models and bioinformatics support to accelerate this causal dissection.
Contact EDITGENE today to design your custom CRISPR model for interleukin-22 binding research.
Frequently Asked Questions About interleukin-22 binding
What is interleukin-22 binding?
Interleukin-22 binding (GO:0042017) is the molecular function of binding to the cytokine interleukin-22, primarily mediated by the IL-22R1/IL-10R2 receptor complex and modulated by the soluble decoy IL-22BP.
What genes are involved in interleukin-22 binding?
Key genes include IL22 (ligand), IL22RA1 and IL10RB (receptor subunits), and IL22RA2 (soluble decoy IL-22BP), with downstream signaling through JAK1, TYK2, and STAT3.
What is the GO ID for interleukin-22 binding?
The Gene Ontology ID for interleukin-22 binding is GO:0042017, classified under molecular_function.
How does IL-22 binding activate signaling?
IL-22 binds IL-22R1, recruits IL-10R2, and activates JAK-STAT signaling, leading to expression of antimicrobial peptides and tissue repair genes.
What is the role of IL-22BP in IL-22 binding?
IL-22BP (IL22RA2) is a soluble decoy receptor that binds IL-22 and prevents it from engaging the membrane receptor, thereby modulating IL-22 bioavailability.
Is interleukin-22 binding involved in disease?
Yes, dysregulated IL-22 binding is implicated in polycystic ovary syndrome, psoriasis, metabolic disorders, trauma outcomes, and cancer metastasis.
How can I study interleukin-22 binding with CRISPR?
CRISPR knockout, knock-in, point-mutation, and overexpression models of IL22, IL22RA1, IL10RB, and IL22RA2 enable causal testing of IL-22 binding in disease-relevant cells.
What cell types express the IL-22 receptor?
IL-22R1 is expressed mainly on epithelial cells, keratinocytes, hepatocytes, and stromal cells, restricting IL-22 binding to non-hematopoietic tissues.
Does IL-22 binding affect the gut microbiome?
The gut microbiota-bile acid-IL-22 axis regulates IL-22 production and binding, linking microbial metabolism to host immune and metabolic homeostasis.
What readouts measure IL-22 binding activity?
Phospho-STAT3 immunoblot, RNA-seq of target genes such as REG3A and MUC1, ELISA for IL-22 and IL-22BP, and organoid Paneth cell formation are common readouts.
Conclusion
Interleukin-22 binding (GO:0042017) is a central molecular function that governs how IL-22 communicates with epithelial and stromal cells to regulate immunity, metabolism, and tissue repair. The interplay between the membrane receptor IL-22R1/IL-10R2 and the soluble decoy IL-22BP determines the intensity and duration of IL-22 signaling, with profound implications for diseases ranging from polycystic ovary syndrome to cancer metastasis. CRISPR-based models of IL22, IL22RA1, IL10RB, and IL22RA2 provide the causal tools needed to translate these insights into therapeutic strategies.
References
- 1. Qi X et al.. 2019. Gut microbiota-bile acid-interleukin-22 axis orchestrates polycystic ovary syndrome.. Nat Med 25(8):1225-1233 PMID: 31332392
- 2. He GW et al.. 2022. Optimized human intestinal organoid model reveals interleukin-22-dependency of paneth cell formation.. Cell Stem Cell 29(9):1333-1345.e6 PMID: 36002022
- 3. Briukhovetska D et al.. 2023. T cell-derived interleukin-22 drives the expression of CD155 by cancer cells to suppress NK cell function and promote metastasis.. Immunity 56(1):143-161.e11 PMID: 36630913
- 4. Anderson AE et al.. 2025. Interleukin-22 and interleukin-22 binding protein signaling axis influences intubation status in trauma.. Surgery 187:109608 PMID: 40857975
- 5. Aksun S et al.. 2023. Interleukin-22/Interleukin-22 binding protein axis and oral contraceptive use in polycystic ovary syndrome.. Endocrine 81(1):54-57 PMID: 37012532
- 6. Wang Z et al.. 2021. Autophagy-based unconventional secretion of HMGB1 by keratinocytes plays a pivotal role in psoriatic skin inflammation.. Autophagy 17(2):529-552 PMID: 32019420
- 7. Gu J et al.. 2022. Down-regulating Interleukin-22/Interleukin-22 binding protein axis promotes inflammation and aggravates diet-induced metabolic disorders.. Mol Cell Endocrinol 557:111776 PMID: 36108991
- 8. Lindahl H et al.. 2021. Interleukin-22 Influences the Th1/Th17 Axis.. Front Immunol 12:618110 PMID: 33692792
