GO:0034685 integrin alphav-beta6 complex: Components, Assembly and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0034685 describes the integrin alphav-beta6 complex, a heterodimeric cell-surface receptor composed of one ITGAV (alphav) subunit and one ITGB6 (beta6) subunit.
• The alpha-v-beta6 integrin is a major activator of latent TGF-beta1 by binding to the RGD motif in latency-associated peptide (LAP) and inducing conformational change.
• This complex is minimally expressed in healthy adult epithelia but is strongly induced after injury, inflammation, or in fibrosis and cancer.
• Alpha-v-beta6 is a therapeutic target in idiopathic pulmonary fibrosis, radiation-induced lung fibrosis, and inflammatory bowel disease, with anti-alpha-v-beta6 antibodies and small-molecule inhibitors under development.
• In arrhythmogenic cardiomyopathy, defective desmosomal adhesion triggers an integrin-alphaV-beta6/TGF-beta signaling cascade that contributes to disease pathogenesis.
• CRISPR-based knockout, knock-in, and overexpression models are essential to dissect the causal roles of ITGAV and ITGB6 in TGF-beta activation and disease.
Description
The integrin alphav-beta6 complex (GO:0034685) is a heterodimeric transmembrane receptor consisting of one alphav (ITGAV) subunit and one beta6 (ITGB6) subunit. It belongs to the integrin family of cell adhesion receptors and is unique among integrins for its restricted expression pattern and its ability to bind and activate latent transforming growth factor-beta1 (TGF-beta1). Unlike many integrins that are broadly expressed, alpha-v-beta6 is barely detectable in normal adult epithelia but is rapidly upregulated in response to tissue injury, inflammation, and oncogenic transformation. This tight regulation makes it a critical sensor of tissue damage and a key mediator of fibrosis and cancer progression. Researchers study GO:0034685 to understand how cell-matrix interactions control TGF-beta bioavailability and to develop targeted therapies for fibrotic and inflammatory diseases. The complex is also implicated in arrhythmogenic cardiomyopathy through a desmosome-integrin signaling axis. Given its central role in TGF-beta activation, the alpha-v-beta6 integrin is a prime target for therapeutic intervention in conditions such as pulmonary fibrosis and ulcerative colitis.
integrin alphav-beta6 complex At A Glance
| GO ID | GO:0034685 |
|---|---|
| GO term | integrin alphav-beta6 complex |
| Ontology | cellular_component |
| Synonym | alphav-beta6 integrin complex, ITGAV-ITGB6 complex |
| Major function | Cell adhesion receptor and activator of latent TGF-beta1 |
| Subunits | ITGAV (alphav) and ITGB6 (beta6) |
| Expression pattern | Low in normal epithelia; induced by injury, inflammation, and cancer |
| Ligand | Latency-associated peptide (LAP) of latent TGF-beta1 via RGD motif |
| Associated diseases | Pulmonary fibrosis, ulcerative colitis, arrhythmogenic cardiomyopathy |
What Is GO:0034685?
According to the Gene Ontology, GO:0034685 (integrin alphav-beta6 complex) is defined as an integrin complex that comprises one alphav subunit and one beta6 subunit. This heterodimeric receptor is a cellular component located at the plasma membrane, where it mediates cell adhesion to the extracellular matrix and activates latent TGF-beta1.
Why Is integrin alphav-beta6 complex Important in Cell Biology?
The integrin alphav-beta6 complex is critically important because it serves as a primary mechanism for activating latent TGF-beta1, a master regulator of fibrosis, inflammation, and cell growth. Its expression is tightly linked to tissue injury and disease states, making it both a biomarker and a therapeutic target. Understanding GO:0034685 is essential for researchers in fibrosis, cancer, and immunology, as modulating this complex can alter TGF-beta signaling and disease outcomes.
• Activates latent TGF-beta1 by binding to the RGD motif in LAP and inducing conformational change.
• Upregulated in response to tissue injury and inflammation, serving as a sensor of epithelial damage.
• Drives pulmonary fibrosis and radiation-induced lung fibrosis; inhibition prevents fibrosis in preclinical models.
• Targeted by anti-alpha-v-beta6 antibodies in ulcerative colitis, with carotegrast methyl in clinical trials.
• Involved in arrhythmogenic cardiomyopathy through a desmosomal-integrin-TGF-beta signaling cascade.
• Expressed in multiple cancers and promotes tumor progression via TGF-beta activation.
• Small-molecule inhibitors of alpha-v-beta6 are being developed for fibrosis and cancer.
• Autoantibodies against alpha-v-beta6 are found in inflammatory bowel disease and vary by population.
• Its restricted expression makes it an attractive target for precision therapy with reduced off-target effects.
• CRISPR models enable causal dissection of ITGAV and ITGB6 in disease pathways.
What Happens During integrin alphav-beta6 complex?
Assembly and Surface Expression
In simple terms: The alpha-v and beta-6 subunits pair up inside the cell and travel to the cell surface together.
The integrin alphav-beta6 complex is formed by non-covalent heterodimerization of the ITGAV and ITGB6 subunits in the endoplasmic reticulum. Proper assembly requires chaperones, and the complex is then transported to the plasma membrane. Expression of ITGB6 is rate-limiting and is induced by injury, inflammation, and growth factors, while ITGAV is more broadly expressed. Once at the surface, the complex adopts an inactive, bent conformation until activated by ligand binding or inside-out signaling.
Ligand Binding and Activation
In simple terms: The integrin grabs onto a specific sequence in the latent TGF-beta complex, which triggers a shape change that releases active TGF-beta.
The alpha-v-beta6 integrin binds with high affinity to the RGD motif present in the latency-associated peptide (LAP) of latent TGF-beta1. This binding is mediated by the beta6 subunit's specificity for the RGD sequence. Upon binding, the integrin undergoes conformational changes that transmit force to the LAP, leading to the release of active TGF-beta1. This activation process is a key step in TGF-beta signaling and is unique to alpha-v-beta6 and alpha-v-beta8 among integrins.
TGF-beta Activation and Signaling
In simple terms: Once released, active TGF-beta binds to its receptors on the cell surface and turns on signaling pathways that control fibrosis and inflammation.
The active TGF-beta1 released by alpha-v-beta6 binds to TGF-beta receptor type II (TGFBR2), which recruits and phosphorylates TGFBR1, leading to SMAD2/3 phosphorylation and nuclear translocation. This canonical signaling drives expression of pro-fibrotic genes such as collagen and fibronectin. In arrhythmogenic cardiomyopathy, defective desmosomes trigger an integrin-alphaV-beta6/TGF-beta cascade that contributes to fibrotic remodeling. Thus, the complex directly links cell adhesion to transcriptional programs.
Regulation of Expression and Activity
In simple terms: The amount of this integrin on the cell surface is controlled by injury signals and inflammatory cytokines, and its activity can be switched on or off.
ITGB6 expression is induced by TGF-beta itself, creating a positive feedback loop, as well as by inflammatory cytokines and growth factors. In inflammatory bowel disease, anti-alpha-v-beta6 autoantibodies may modulate its function. Small-molecule inhibitors and antibodies can block ligand binding and TGF-beta activation. The complex is also regulated by inside-out signaling that controls its affinity for LAP.
Downstream Consequences in Disease
In simple terms: When this integrin is overactive, it drives excessive scarring and inflammation in organs like the lungs and gut.
In pulmonary fibrosis, alpha-v-beta6-mediated TGF-beta activation promotes fibroblast proliferation and collagen deposition; inhibition prevents radiation-induced lung fibrosis in mice. In ulcerative colitis, alpha-v-beta6 is upregulated and anti-alpha-v-beta6 antibodies are being tested as therapy. In arrhythmogenic cardiomyopathy, the integrin-alphaV-beta6/TGF-beta cascade contributes to fibrotic replacement of myocardium. These disease links underscore the importance of precise regulation.
Key Genes Involved in GO:0034685 integrin alphav-beta6 complex
The following genes and proteins are central to the biology of the integrin alphav-beta6 complex.
| Gene | Major Role | Research Relevance |
|---|---|---|
| ITGAV | Encodes the alpha-v integrin subunit; forms heterodimer with beta6 | Knockout causes loss of alpha-v-beta6 complex; used to study TGF-beta activation |
| ITGB6 | Encodes the beta-6 integrin subunit; confers RGD-binding specificity | Inducible expression; knockout prevents fibrosis in models |
| TGFB1 | Encodes latent TGF-beta1; activated by alpha-v-beta6 | Key downstream effector; mutations affect fibrosis and immunity |
| LAP (part of TGFB1) | Latency-associated peptide; contains RGD motif bound by alpha-v-beta6 | Target for blocking antibodies and inhibitors |
| TGFBR2 | TGF-beta receptor type II; binds active TGF-beta | Mediates downstream SMAD signaling |
| TGFBR1 | TGF-beta receptor type I; phosphorylated by TGFBR2 | Propagates canonical signaling |
| SMAD2/3 | Intracellular signal transducers | Readout of TGF-beta pathway activation |
| SMAD4 | Co-SMAD; forms complex with SMAD2/3 | Required for transcriptional responses |
| COL1A1 | Type I collagen; pro-fibrotic target gene | Marker of fibrosis in vitro and in vivo |
| FN1 | Fibronectin; extracellular matrix protein | Upregulated by TGF-beta; promotes fibrosis |
| ACTA2 | Alpha-smooth muscle actin; myofibroblast marker | Indicator of fibroblast activation |
| DSP | Desmoplakin; desmosomal protein | Mutations cause arrhythmogenic cardiomyopathy via integrin-alphaV-beta6 |
| PKP2 | Plakophilin-2; desmosomal protein | Linked to arrhythmogenic cardiomyopathy and integrin signaling |
| JUP | Plakoglobin; desmosomal protein | Involved in desmosome-integrin crosstalk |
| ITGB8 | Beta-8 integrin subunit; also activates TGF-beta | Related integrin with overlapping functions |
| LTBP1 | Latent TGF-beta binding protein | Regulates TGF-beta sequestration and presentation |
| MMP2 | Matrix metalloproteinase-2 | Remodels ECM downstream of TGF-beta |
| MMP9 | Matrix metalloproteinase-9 | Inflammation-associated protease |
How Is integrin alphav-beta6 complex Regulated?
The expression and activity of the integrin alphav-beta6 complex are tightly regulated at multiple levels. ITGB6 gene expression is induced by TGF-beta1 itself, forming a positive feedback loop that amplifies fibrosis. Inflammatory cytokines such as IL-1beta and TNF-alpha also upregulate ITGB6 in epithelial cells. At the protein level, the complex can be regulated by inside-out signaling that modulates its affinity for the RGD motif in LAP. Additionally, anti-alpha-v-beta6 autoantibodies may block or modulate its function in inflammatory bowel disease. Small-molecule inhibitors and therapeutic antibodies can interfere with ligand binding and downstream TGF-beta activation.
integrin alphav-beta6 complex and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| ITGB6 | Pulmonary fibrosis | Itgb6 knockout mice; bleomycin-induced lung fibrosis model |
| ITGAV | Arrhythmogenic cardiomyopathy | Cardiomyocyte-specific Itgav knockout; desmosomal mutation knock-in |
| ITGB6 | Ulcerative colitis | Intestinal epithelial cell-specific knockout; DSS-induced colitis |
| TGFB1 | Fibrosis and inflammation | Tgfb1 knockout or conditional knock-in; reporter mice |
| DSP | Arrhythmogenic cardiomyopathy | Dsp knockout or point mutation knock-in in cardiomyocytes |
Pulmonary Fibrosis
The integrin alphav-beta6 complex is a key activator of latent TGF-beta1 in the lung, and its inhibition prevents radiation-induced lung fibrosis in preclinical models. In idiopathic pulmonary fibrosis, alpha-v-beta6 is upregulated on injured alveolar epithelium and drives fibroblast activation and collagen deposition. Targeting this complex with antibodies or small molecules is a promising therapeutic strategy.
Inflammatory Bowel Disease and Ulcerative Colitis
Alpha-v-beta6 is overexpressed in the inflamed intestinal epithelium of ulcerative colitis patients, and anti-alpha-v-beta6 antibodies are detectable in sera, with differences between U.S. and Japanese cohorts. Carotegrast methyl, an alpha-4 integrin antagonist, has been studied in ulcerative colitis, and alpha-v-beta6 is being explored as a therapeutic target. The complex contributes to TGF-beta activation and mucosal fibrosis in IBD.
Arrhythmogenic Cardiomyopathy
Defective desmosomal adhesion in arrhythmogenic cardiomyopathy triggers an integrin-alphaV-beta6/TGF-beta signaling cascade that promotes fibrotic remodeling of the heart. Mutations in desmosomal genes such as DSP, PKP2, and JUP lead to increased alpha-v-beta6 activity and TGF-beta release, contributing to disease progression. This highlights the complex's role beyond epithelial tissues.
Cancer
Alpha-v-beta6 is frequently upregulated in carcinomas and promotes tumor progression through TGF-beta activation, which enhances invasion, metastasis, and immune evasion. Its restricted expression in normal tissues makes it an attractive target for cancer imaging and therapy. Small-molecule inhibitors of alpha-v-beta6 are being developed to block these pro-tumorigenic effects.
From integrin alphav-beta6 complex-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of ITGB6 prevent TGF-beta activation? | ITGB6 knockout cell line (e.g., A549, HaCaT) |
| Does a point mutation in the RGD-binding site of ITGB6 abolish ligand binding? | ITGB6 point-mutation knock-in via CRISPR |
| Can we track alpha-v-beta6 complex localization in live cells? | ITGB6 tagged knock-in with fluorescent protein |
| Does overexpression of ITGB6 drive fibrosis in vitro? | ITGB6 overexpression in epithelial cells |
| What is the role of ITGAV in arrhythmogenic cardiomyopathy? | Cardiomyocyte-specific ITGAV knockout in iPSC-derived cardiomyocytes |
| Can we identify genes that regulate ITGB6 expression? | Genome-wide CRISPR library screening |
How to Study the integrin alphav-beta6 complex Process
| Method | What It Measures | Typical Application |
|---|---|---|
| CRISPR knockout | Loss of ITGAV or ITGB6 function | Determine necessity in TGF-beta activation |
| CRISPR knock-in | Point mutations in ITGB6 RGD-binding site | Test ligand specificity |
| RNA-seq | Transcriptional changes | Identify TGF-beta target genes |
| Proteomics | Protein expression and interactions | Map signaling complexes |
| Immunofluorescence | Subcellular localization | Track integrin trafficking |
| Cell adhesion assay | Binding to LAP or ECM | Quantify integrin function |
| ELISA | Active TGF-beta levels | Measure activation capacity |
| CRISPR library screening | Genes regulating ITGB6 expression | Identify novel modulators |
CRISPR Knockout and Knock-in Models
CRISPR-Cas9 gene editing enables the generation of ITGAV or ITGB6 knockout cell lines and animal models to study loss-of-function phenotypes. Knock-in of point mutations in the RGD-binding domain of ITGB6 can dissect ligand specificity. These models are essential for causal inference in TGF-beta activation and fibrosis.
Transcriptomic and Proteomic Profiling
RNA-seq and proteomics can quantify changes in TGF-beta target genes (e.g., COL1A1, FN1) and identify signaling networks downstream of alpha-v-beta6. Phosphoproteomics can reveal SMAD activation dynamics.
Imaging and Cell Adhesion Assays
Fluorescence microscopy of tagged integrins and cell adhesion assays on LAP-coated surfaces measure complex localization and function. Live-cell imaging can track internalization and recycling.
Therapeutic Antibody and Inhibitor Testing
Anti-alpha-v-beta6 antibodies and small-molecule inhibitors can be tested in cell-based TGF-beta activation assays and animal models of fibrosis. These studies inform clinical development for ulcerative colitis and pulmonary fibrosis.
How CRISPR Can Be Used to Study GO:0034685 integrin alphav-beta6 complex
Knockout
CRISPR knockout of ITGAV or ITGB6 abolishes the alpha-v-beta6 complex, preventing TGF-beta activation and reducing fibrosis in vitro and in vivo. These models are used to validate therapeutic targets and understand disease mechanisms.
Point Mutation
Point mutations in the RGD-binding pocket of ITGB6 can be introduced to dissect ligand specificity and downstream signaling. Such models help distinguish between integrin-mediated adhesion and TGF-beta activation.
Knock-in
Knock-in of fluorescent tags or epitope tags into ITGAV or ITGB6 allows real-time tracking of complex assembly and trafficking. Knock-in of disease-associated mutations (e.g., in DSP) can model arrhythmogenic cardiomyopathy.
Overexpression
Overexpression of ITGB6 in epithelial cells drives TGF-beta activation and pro-fibrotic gene expression, mimicking injury states. This approach is useful for gain-of-function studies and drug screening.
How EDITGENE Supports integrin alphav-beta6 complex Research
Researchers studying integrin alphav-beta6 complex-related genes often need to determine whether a candidate gene is causally involved in TGF-beta activation, fibrosis, or inflammation. EDITGENE provides a comprehensive suite of CRISPR services to generate precisely engineered cell models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for integrin alphav-beta6 complex research.
Frequently Asked Questions About integrin alphav-beta6 complex
What is the integrin alphav-beta6 complex?
It is a heterodimeric cell-surface receptor composed of ITGAV and ITGB6 subunits that binds to latent TGF-beta1 and activates it.
What genes are involved in the integrin alphav-beta6 complex?
The core genes are ITGAV and ITGB6, which encode the two subunits. Downstream effectors include TGFB1, TGFBR1, TGFBR2, and SMAD2/3.
What is the function of GO:0034685?
GO:0034685 represents the integrin alphav-beta6 complex, which mediates cell adhesion and activates latent TGF-beta1, a key driver of fibrosis and inflammation.
Which diseases are associated with integrin alphav-beta6?
It is implicated in pulmonary fibrosis, radiation-induced lung fibrosis, ulcerative colitis, arrhythmogenic cardiomyopathy, and cancer.
How is the integrin alphav-beta6 complex regulated?
Its expression is induced by TGF-beta and inflammatory cytokines, and its activity is controlled by inside-out signaling and autoantibodies.
What experimental models are used to study integrin alphav-beta6?
CRISPR knockout and knock-in cell lines, animal models of fibrosis, and patient-derived organoids are commonly used.
Can CRISPR be used to target ITGB6?
Yes, CRISPR knockout of ITGB6 abolishes the complex and prevents TGF-beta activation in preclinical models.
What are the therapeutic strategies targeting alpha-v-beta6?
Anti-alpha-v-beta6 antibodies and small-molecule inhibitors are being developed for fibrosis and ulcerative colitis.
Is alpha-v-beta6 expressed in normal tissues?
It is minimally expressed in healthy adult epithelia but is strongly induced after injury, inflammation, or in cancer.
How does alpha-v-beta6 activate TGF-beta?
It binds to the RGD motif in the latency-associated peptide (LAP) of latent TGF-beta1, inducing a conformational change that releases active TGF-beta.
Conclusion
The integrin alphav-beta6 complex (GO:0034685) is a critical mediator of TGF-beta activation and a key player in fibrosis, inflammation, and cancer. Its unique expression pattern and central role in disease make it an attractive therapeutic target. CRISPR-based models are indispensable for dissecting its function and for preclinical drug development. EDITGENE provides comprehensive services to accelerate research on this complex.
References
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- 3. Matsuoka K et al.. 2025. Optimising carotegrast methyl use in ulcerative colitis: patient profiling, predictive biomarkers, and timing of efficacy evaluation (ASPECT study).. J Gastroenterol 60(12):1523-1534 PMID: 40982097
- 4. Schinner C et al.. 2022. Defective Desmosomal Adhesion Causes Arrhythmogenic Cardiomyopathy by Involving an Integrin-αVβ6/TGF-β Signaling Cascade.. Circulation 146(21):1610-1626 PMID: 36268721
- 5. Mendieta-Escalante EA et al.. 2025. Current and Emerging Autoantibodies in Ulcerative Colitis.. Eur J Immunol 55(8):e51721 PMID: 40762088
- 6. Kakuta Y et al.. 2026. Differences in Anti-αvβ6 Integrin Antibody Expression between U.S. and Japanese Cohorts in Inflammatory Bowel Disease.. Inflamm Bowel Dis 32(1):130-140 PMID: 41274279
- 7. Guest EE et al.. 2020. Molecular Simulation of αvβ6 Integrin Inhibitors.. J Chem Inf Model 60(11):5487-5498 PMID: 32421320
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