GO:0034675 integrin alpha6-beta1 complex: Components, Assembly and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0034675 (integrin alpha6-beta1 complex) is a heterodimeric cell-surface adhesion receptor composed of one ITGA6 (alpha6) subunit and one ITGB1 (beta1) subunit.
• The complex is a major laminin-binding integrin, mediating attachment of cells to laminin-rich basement membranes in liver, kidney, mammary gland, endometrium and placenta.
• ITGA6-ITGB1 is compartmentalized to specific membrane domains, such as the sperm equatorial segment, where it supports fertilization-related adhesion.
• In cancer, alpha6beta1 cooperates with tetraspanins such as CO-029 and CD151 to promote motility and invasion of pancreatic adenocarcinoma cells.
• Expression of ITGA6 and ITGB1 is developmentally and hormonally regulated, with distinct mRNA and protein profiles during mammary gland development and carcinogenesis.
• CRISPR knockout, point-mutation, knock-in and overexpression models enable causal dissection of ITGA6-ITGB1 function in adhesion, migration and tissue morphogenesis.
Description
The integrin alpha6-beta1 complex (GO:0034675) is a heterodimeric transmembrane adhesion receptor in which the alpha6 subunit (ITGA6) pairs with the beta1 subunit (ITGB1). It belongs to the cellular_component ontology and is one of the principal laminin-binding integrins, linking the extracellular matrix to the cytoskeleton and to intracellular signaling. Because it recognizes laminins in basement membranes, the complex is central to epithelial and endothelial adhesion, tissue morphogenesis and cell migration. Researchers study GO:0034675 to understand how cells attach to laminin-rich matrices, how this adhesion is remodeled during development, and how its dysregulation contributes to cancer and other pathologies. The complex has been detected in diverse contexts, including hepatoma cells attaching to laminin, ureteric bud branching during kidney development, pancreatic adenocarcinoma, the mammary gland, the maternal-fetal interface, and decidualized endometrial stromal cells. Its compartmentalization in specialized membrane domains, such as the sperm equatorial segment, further illustrates its functional versatility. This article summarizes the QuickGO definition, the structure and assembly of the complex, its molecular mechanism, the genes involved, disease links, and the CRISPR-based methods used to study it.
integrin alpha6-beta1 complex At A Glance
| GO ID | GO:0034675 |
|---|---|
| GO term | integrin alpha6-beta1 complex |
| Ontology | cellular_component |
| Synonym | alpha6-beta1 integrin complex; ITGA6-ITGB1 complex; VLA-6 complex |
| Definition | An integrin complex that comprises one alpha6 subunit and one beta1 subunit. |
| Major function | Laminin-binding adhesion receptor that mediates cell attachment to basement membranes and links the extracellular matrix to intracellular signaling. |
| Subunit composition | One ITGA6 (alpha6) subunit and one ITGB1 (beta1) subunit. |
| Representative ligands | Laminins, including laminin-5 (laminin-332) in epithelial basement membranes. |
| Representative contexts | Hepatoma cell attachment, kidney ureteric bud branching, pancreatic adenocarcinoma motility, mammary gland development, maternal-fetal interface, decidualized endometrium, sperm. |
What Is GO:0034675?
GO:0034675, integrin alpha6-beta1 complex, is defined by QuickGO as an integrin complex that comprises one alpha6 subunit and one beta1 subunit. In other words, it is a non-covalent heterodimer of the ITGA6 and ITGB1 proteins that forms a functional laminin-binding adhesion receptor at the cell surface. The complex is also known as the alpha6-beta1 integrin complex, ITGA6-ITGB1 complex, or VLA-6 complex.
Why Is integrin alpha6-beta1 complex Important in Cell Biology?
The integrin alpha6-beta1 complex is important because it is a primary cellular receptor for laminins, the major adhesive proteins of basement membranes, and therefore governs how epithelial, endothelial and other cells attach to, migrate on, and remodel their surrounding matrix. Its activity influences fundamental processes such as kidney branching morphogenesis, mammary gland development, embryo implantation and placentation, and sperm function. In cancer, alpha6beta1 contributes to the attachment and motility of tumor cells, including hepatoma and pancreatic adenocarcinoma cells, and its cooperation with tetraspanins can enhance invasive behavior. Because the complex sits at the interface between the extracellular environment and intracellular signaling, it is a focal point for research on adhesion, tissue architecture, development and metastasis.
• Mediates cell attachment to laminin-rich basement membranes, a fundamental adhesion function.
• Drives branching morphogenesis of the ureteric bud during kidney development.
• Supports normal mammary gland development and is differentially expressed during carcinogenesis.
• Participates in maternal-fetal interface interactions during pregnancy.
• Is induced in decidualized human endometrial stromal cells, linking it to implantation biology.
• Promotes hepatoma cell attachment to laminin, relevant to liver cancer biology.
• Cooperates with tetraspanins CO-029 and CD151 to influence pancreatic adenocarcinoma cell motility.
• Shows compartmentalized localization in sperm, suggesting specialized roles in fertilization.
• Serves as a model heterodimer for studying integrin alpha/beta pairing and signaling.
• Provides a tractable target for CRISPR-based functional genomics of adhesion and migration.
Structure, Assembly and Molecular Mechanism of the integrin alpha6-beta1 complex
Heterodimerization of ITGA6 and ITGB1
In simple terms: The complex is built from two different protein subunits that pair up to form one functional receptor.
The integrin alpha6-beta1 complex is a non-covalent heterodimer containing one alpha6 (ITGA6) subunit and one beta1 (ITGB1) subunit. This pairing is the defining feature of GO:0034675 and is required for the complex to be recognized as a functional integrin at the cell surface. The heterodimer is the unit that binds laminin and transmits signals, rather than either subunit alone.
Laminin recognition and cell attachment
In simple terms: The paired receptor grabs onto laminin proteins in the matrix, anchoring the cell in place.
The alpha6-beta1 complex functions as a laminin-binding integrin that mediates attachment of cells to laminin substrates. In hepatoma cells, alpha6beta1 plays a significant role in attachment to laminin. During kidney development, laminin-binding integrins including alpha6beta1 participate in ureteric bud branching morphogenesis, where interactions with laminin-5 and other basement membrane components shape epithelial outgrowth. Laminin-5 (laminin-332) is a well-characterized ligand for laminin-binding integrins in epithelial tissues.
Membrane compartmentalization and specialized adhesion sites
In simple terms: The receptor is not spread evenly over the cell; it is concentrated in specific patches where adhesion needs to happen.
Specific integrin heterodimers, including alpha6-beta1, are compartmentalized in distinct membrane domains. In mouse sperm, alpha6-beta1 is localized to particular regions such as the equatorial segment, indicating that its function is spatially restricted. In pancreatic adenocarcinoma cells, alpha6beta1 colocalizes with the tetraspanins CO-029 and CD151, forming membrane complexes that influence cell motility. This compartmentalization allows the same heterodimer to serve different functions in different cell types.
Developmental and hormonal regulation of expression
In simple terms: Cells adjust how much of the receptor they make depending on developmental stage and hormonal signals.
Expression of integrin alpha6 and beta1 mRNAs and proteins changes during normal rat mammary gland development and in carcinogenesis, indicating developmental regulation. In the rhesus monkey, integrins and their extracellular matrix ligands show temporal and spatial expression at the maternal-fetal interface during pregnancy. In human endometrial stromal cells, alpha6beta1 expression is induced by 8-Br-cAMP during in vitro decidualization, demonstrating hormonal/cAMP-dependent regulation.
Cooperation with tetraspanins and signaling
In simple terms: The receptor teams up with other membrane proteins to send signals that change how cells move.
The alpha6-beta1 complex associates with tetraspanins such as CO-029 and CD151 in human pancreatic adenocarcinoma, and this colocalization impacts cell motility. Such partnerships link the integrin to intracellular signaling pathways that control migration and invasion. In hepatoma cells, alpha6beta1-mediated attachment to laminin is functionally significant, supporting the idea that the complex transduces adhesion-dependent signals.
Key Genes Involved in GO:0034675 integrin alpha6-beta1 complex
The integrin alpha6-beta1 complex is encoded by two principal genes, ITGA6 and ITGB1, whose products form the heterodimer; additional genes influence its ligands, trafficking and signaling partners.
| Gene | Major Role | Research Relevance |
|---|---|---|
| ITGA6 | Encodes the alpha6 integrin subunit that pairs with beta1 to form the complex | Core subunit for knockout and knock-in studies of GO:0034675 |
| ITGB1 | Encodes the beta1 integrin subunit that pairs with alpha6 | Essential partner subunit; beta1 is shared with other integrins |
| LAMA3 | Encodes a laminin subunit of laminin-5 (laminin-332), a ligand for laminin-binding integrins | Ligand-side manipulation to test alpha6beta1-dependent adhesion |
| LAMB3 | Encodes a laminin subunit of laminin-5 | Ligand-side manipulation in basement membrane studies |
| LAMC2 | Encodes a laminin subunit of laminin-5 | Ligand-side manipulation in basement membrane studies |
| CD151 | Tetraspanin that colocalizes with alpha6beta1 and modulates motility | Co-receptor for motility assays in pancreatic adenocarcinoma |
| CO-029 | Tetraspanin that colocalizes with alpha6beta1 in pancreatic adenocarcinoma | Co-receptor for motility assays |
| ITGA3 | Alpha3 subunit that pairs with beta1 to form alpha3beta1, another laminin-binding integrin | Comparative control for alpha6beta1 specificity |
| ITGB4 | Beta4 subunit that partners with alpha6 in hemidesmosomes (distinct from alpha6beta1) | Discriminating alpha6beta1 from alpha6beta4 functions |
| LAMA1 | Laminin subunit present in basement membranes | Matrix-side studies of integrin-ligand interactions |
| LAMA5 | Laminin subunit present in basement membranes | Matrix-side studies of integrin-ligand interactions |
| LAMB1 | Laminin subunit present in basement membranes | Matrix-side studies of integrin-ligand interactions |
| LAMC1 | Laminin subunit present in basement membranes | Matrix-side studies of integrin-ligand interactions |
| NID1 | Basement membrane component influencing integrin-mediated adhesion | Contextual matrix studies |
| HSPG2 | Perlecan, a basement membrane proteoglycan influencing adhesion | Contextual matrix studies |
| COL4A1 | Type IV collagen, a basement membrane component | Contextual matrix studies |
| COL4A2 | Type IV collagen, a basement membrane component | Contextual matrix studies |
| FN1 | Fibronectin, an extracellular matrix protein influencing integrin signaling | Comparative matrix ligand studies |
How Is integrin alpha6-beta1 complex Regulated?
The integrin alpha6-beta1 complex is regulated at multiple levels. Its expression is developmentally controlled, as shown by differential integrin mRNA and protein profiles during normal rat mammary gland development and carcinogenesis. Hormonal and cAMP-dependent signals regulate the complex in the reproductive tract: in human endometrial stromal cells, 8-Br-cAMP-induced decidualization is accompanied by changes in integrin expression, and in the rhesus monkey, integrins and their extracellular matrix ligands display temporal and spatial expression at the maternal-fetal interface during pregnancy. Ligand availability also regulates function, since the complex binds laminins such as laminin-5 in basement membranes. In cancer cells, association with tetraspanins such as CO-029 and CD151 modulates alpha6beta1-dependent motility, providing an additional layer of regulation. Finally, compartmentalization within specific membrane domains, as seen in sperm, restricts where the complex acts.
integrin alpha6-beta1 complex and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| ITGA6 | Hepatoma cell attachment to laminin | ITGA6 knockout hepatoma cell lines with laminin adhesion assays |
| ITGB1 | Pancreatic adenocarcinoma motility | ITGB1 knockout pancreatic cancer cells with motility assays |
| ITGA6/ITGB1 | Kidney branching morphogenesis defects | Conditional knockout in ureteric bud organ culture |
| ITGA6/ITGB1 | Implantation and decidualization defects | Endometrial stromal cell models with cAMP-induced decidualization |
| ITGA6/ITGB1 | Mammary gland carcinogenesis | Mammary epithelial cell lines and rodent models |
Cancer: hepatoma and pancreatic adenocarcinoma
The integrin alpha6-beta1 complex contributes to tumor cell adhesion and motility. In hepatoma cells, alpha6beta1 plays a significant role in attachment to laminin, supporting liver cancer cell interactions with basement membrane matrices. In human pancreatic adenocarcinoma, alpha6beta1 colocalizes with the tetraspanins CO-029 and CD151, and this colocalization impacts cell motility, suggesting a role in invasion and metastasis. Laminin-5, a ligand for laminin-binding integrins, is deposited in colorectal adenomas and carcinomas, further linking this adhesion axis to tumor biology.
Developmental and reproductive disorders
Because alpha6beta1 mediates laminin-dependent morphogenesis, its dysfunction may affect organ development. Laminin-binding integrins including alpha6beta1 are involved in branching morphogenesis of the ureteric bud during kidney development, a process essential for normal kidney formation. In the reproductive system, the complex is expressed at the maternal-fetal interface during pregnancy in the rhesus monkey and is induced in decidualized human endometrial stromal cells, implicating it in implantation and placentation. In sperm, compartmentalized alpha6beta1 may contribute to fertilization-related adhesion events.
Mammary gland pathology
Integrin alpha6 and beta1 expression is differentially regulated during normal rat mammary gland development and in carcinogenesis, indicating that altered expression of the complex may accompany breast tissue pathology. This makes the mammary gland a useful model for studying how developmental regulation of alpha6beta1 relates to tumorigenesis.
From integrin alpha6-beta1 complex-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of ITGA6 abolish laminin attachment? | ITGA6 knockout cell lines (e.g., hepatoma) with laminin adhesion assays |
| Is ITGB1 required for pancreatic cancer cell motility? | ITGB1 knockout pancreatic adenocarcinoma cells with migration assays |
| Does alpha6beta1 mediate ureteric bud branching? | Conditional knockout of Itga6 or Itgb1 in mouse ureteric bud organ culture |
| How does cAMP regulate alpha6beta1 during decidualization? | Human endometrial stromal cells with 8-Br-cAMP treatment and knockdown |
| Does tetraspanin co-expression modulate alpha6beta1 motility? | Knock-in or overexpression of CD151/CO-029 in pancreatic cancer cells |
| Is alpha6beta1 compartmentalized in sperm? | Tagged knock-in of ITGA6 or ITGB1 in mouse sperm for imaging |
How to Study the integrin alpha6-beta1 complex Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Cell adhesion assay on laminin | Attachment of cells to laminin substrates | Testing alpha6beta1-dependent adhesion in hepatoma cells |
| Migration/motility assay | Cell movement and invasion | Assessing tetraspanin-alpha6beta1 effects in pancreatic cancer |
| mRNA and protein expression profiling | Levels of ITGA6 and ITGB1 | Comparing normal and carcinogenic mammary gland |
| Immunolocalization/imaging | Spatial distribution of the complex | Mapping compartmentalization in sperm |
| Organ culture of ureteric bud | Branching morphogenesis | Testing laminin-binding integrins in kidney development |
| Decidualization induction with 8-Br-cAMP | Integrin expression changes | Studying alpha6beta1 in endometrial stromal cells |
| Laminin-5 deposition analysis | Ligand availability in tissues | Linking laminin-5 to integrin function in adenomas/carcinomas |
| CRISPR knockout/knock-in | Causal role of ITGA6/ITGB1 | Functional dissection of the complex in multiple models |
Adhesion and migration assays
Functional studies of the integrin alpha6-beta1 complex commonly use cell adhesion assays on laminin substrates to measure attachment, as demonstrated in hepatoma cells where alpha6beta1 plays a significant role in laminin attachment. Migration and motility assays are used to assess how the complex and its tetraspanin partners influence cell movement, as shown in pancreatic adenocarcinoma cells. These assays are typically combined with antibody blocking or genetic perturbation to establish causality.
Expression profiling and imaging
Expression of ITGA6 and ITGB1 can be profiled by mRNA and protein methods across developmental stages, as done in the rat mammary gland during normal development and carcinogenesis. Spatial and temporal expression at the maternal-fetal interface has been mapped in the rhesus monkey, and induction during decidualization has been measured in human endometrial stromal cells. Imaging of tagged subunits allows visualization of compartmentalization, as shown for alpha6beta1 in mouse sperm.
Organ culture and morphogenesis models
Kidney ureteric bud branching morphogenesis is a classic model for studying laminin-binding integrins including alpha6beta1, using organ culture and perturbation of integrin-ligand interactions. Such models allow researchers to test how the complex contributes to epithelial outgrowth and tissue architecture. They can be combined with laminin-5 (laminin-332) deposition studies, since laminin-5 is a ligand for laminin-binding integrins in epithelial tissues.
CRISPR-based perturbation
CRISPR knockout, point mutation, knock-in and overexpression approaches enable precise manipulation of ITGA6 and ITGB1 to test their roles in adhesion, motility and morphogenesis. These methods can be paired with the functional assays described above to link genotype to phenotype. They are particularly useful for dissecting the contributions of the alpha6beta1 heterodimer versus related integrins such as alpha3beta1 or alpha6beta4.
How CRISPR Can Be Used to Study GO:0034675 integrin alpha6-beta1 complex
Knockout
CRISPR knockout of ITGA6 or ITGB1 can abolish formation of the integrin alpha6-beta1 complex, allowing researchers to test its requirement for laminin attachment and motility. For example, knocking out ITGA6 in hepatoma cells would test the reported role of alpha6beta1 in attachment to laminin, while ITGB1 knockout in pancreatic adenocarcinoma cells would probe its contribution to motility. Knockout in organ culture models can reveal roles in branching morphogenesis.
Point Mutation
Point mutations can be introduced into ITGA6 or ITGB1 to dissect specific residues required for heterodimerization, ligand binding or signaling. Because the complex is defined by the pairing of one alpha6 and one beta1 subunit, mutations that disrupt this interface can be used to separate adhesion from downstream signaling. Such mutants are valuable when complete knockout is lethal or when subtle functional changes are being modeled.
Knock-in
Knock-in of tags or reporters into ITGA6 or ITGB1 enables visualization and tracking of the complex in its native context. This is particularly useful for studying compartmentalization, as demonstrated for alpha6beta1 in specific sperm membrane domains. Tagged knock-in lines can also be used to monitor complex assembly and trafficking in epithelial cells.
Overexpression
Overexpression of ITGA6 and ITGB1 can amplify alpha6beta1-dependent adhesion and signaling, providing a gain-of-function counterpart to knockout studies. Overexpression in pancreatic cancer cells can be combined with tetraspanin co-expression to test effects on motility. In mammary epithelial models, overexpression can mimic the altered integrin expression seen during carcinogenesis.
How EDITGENE Supports integrin alpha6-beta1 complex Research
Researchers studying integrin alpha6-beta1 complex-related genes often need to determine whether a candidate gene is causally involved in adhesion, migration or morphogenesis, rather than merely correlated with a phenotype. This requires precise, reproducible genetic models in relevant cell types, such as hepatoma, pancreatic adenocarcinoma, kidney, endometrial and mammary cells. EDITGENE provides the CRISPR tools and services needed to build such models and to interpret the resulting data in the context of published literature on GO:0034675.
Contact EDITGENE today to design your custom CRISPR model for integrin alpha6-beta1 complex research.
Frequently Asked Questions About integrin alpha6-beta1 complex
What is GO:0034675?
GO:0034675 is the Gene Ontology cellular_component term for the integrin alpha6-beta1 complex, defined as an integrin complex that comprises one alpha6 subunit and one beta1 subunit.
What is the integrin alpha6-beta1 complex?
It is a heterodimeric cell-surface adhesion receptor made of ITGA6 and ITGB1 that binds laminins and mediates cell attachment to basement membranes.
What genes are involved in the integrin alpha6-beta1 complex?
The core genes are ITGA6 and ITGB1, which encode the two subunits; ligands include laminin genes such as LAMA3, LAMB3 and LAMC2, and partners include tetraspanins CD151 and CO-029.
What does the integrin alpha6-beta1 complex do?
It mediates attachment of cells to laminin, contributes to tissue morphogenesis and cell motility, and links the extracellular matrix to intracellular signaling.
Where is the integrin alpha6-beta1 complex found?
It has been detected in hepatoma cells, kidney ureteric bud, pancreatic adenocarcinoma, mammary gland, maternal-fetal interface, decidualized endometrium and sperm.
How is the integrin alpha6-beta1 complex regulated?
Its expression is developmentally and hormonally regulated, influenced by ligand availability, and modulated by tetraspanin association and membrane compartmentalization.
Is the integrin alpha6-beta1 complex involved in cancer?
Yes; it supports hepatoma cell attachment to laminin and pancreatic adenocarcinoma cell motility, and its ligand laminin-5 is deposited in colorectal tumors.
How can I study the integrin alpha6-beta1 complex with CRISPR?
CRISPR knockout of ITGA6 or ITGB1, point mutations, tagged knock-ins and overexpression can be combined with adhesion, migration and organ culture assays to test function.
What assays are used to measure integrin alpha6-beta1 function?
Common assays include laminin adhesion, migration/motility, expression profiling, immunolocalization, decidualization induction and ureteric bud organ culture.
Why is the integrin alpha6-beta1 complex important for development?
It mediates laminin-dependent processes such as kidney branching morphogenesis, mammary gland development and implantation-related events at the maternal-fetal interface.
Conclusion
The integrin alpha6-beta1 complex (GO:0034675) is a laminin-binding heterodimer of ITGA6 and ITGB1 that serves as a key interface between cells and basement membranes. Its roles span kidney branching morphogenesis, mammary gland development, implantation biology, sperm function and cancer cell adhesion and motility. Because its function is context-dependent and spatially compartmentalized, precise genetic models are essential for causal analysis. CRISPR-based knockout, point-mutation, knock-in and overexpression approaches, combined with adhesion, migration and organ culture assays, provide a robust framework for dissecting how this complex contributes to normal physiology and disease.
References
- 1. Frolikova M et al.. 2019. Addressing the Compartmentalization of Specific Integrin Heterodimers in Mouse Sperm.. Int J Mol Sci 20(5) PMID: 30813527
- 2. Torimura T et al.. 1999. Integrin alpha6beta1 plays a significant role in the attachment of hepatoma cells to laminin.. J Hepatol 31(4):734-40 PMID: 10551399
- 3. Zent R et al.. 2001. Involvement of laminin binding integrins and laminin-5 in branching morphogenesis of the ureteric bud during kidney development.. Dev Biol 238(2):289-302 PMID: 11784011
- 4. Gesierich S et al.. 2005. Colocalization of the tetraspanins, CO-029 and CD151, with integrins in human pancreatic adenocarcinoma: impact on cell motility.. Clin Cancer Res 11(8):2840-52 PMID: 15837731
- 5. Huang RY et al.. 2001. Differential expression of integrin mRNAs and proteins during normal rat mammary gland development and in carcinogenesis.. Cell Tissue Res 303(1):69-80 PMID: 11236006
- 6. Qin L et al.. 2003. Temporal and spatial expression of integrins and their extracellular matrix ligands at the maternal-fetal interface in the rhesus monkey during pregnancy.. Biol Reprod 69(2):563-71 PMID: 12700193
- 7. Hwang JH et al.. 2002. The characteristics of integrins expression in decidualized human endometrial stromal cell induced by 8-Br-cAMP in in vitro.. Exp Mol Med 34(3):194-200 PMID: 12216111
- 8. Lohi J et al.. 2000. Basement membrane laminin-5 is deposited in colorectal adenomas and carcinomas and serves as a ligand for alpha3beta1 integrin.. APMIS 108(3):161-72 PMID: 10752684
