GO:0140308 insulin-like growth factor binding receptor complex: Components, Assembly and Research Methods, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0140308 describes a plasma membrane-localized protein complex that binds insulin-like growth factors IGF1 or IGF2.
• The class includes signaling receptors such as the IGF1R complex, which has intrinsic tyrosine kinase activity, and non-signaling receptors such as IGF2R, which sequesters IGF2 for lysosomal degradation.
• These complexes regulate cell growth, proliferation, survival, and development by modulating IGF signaling.
• Dysregulation of IGF-binding receptor complexes is implicated in cancer, metabolic disorders, and thyroid disease.
• Key protein components include IGF1R, IGF2R, insulin receptor isoforms, and IGF-binding proteins that modulate ligand availability.
• CRISPR knockout, point mutation, knock-in, and overexpression models enable causal dissection of IGF receptor complex function.
Description
The insulin-like growth factor binding receptor complex (GO:0140308) is a plasma membrane-localized protein assembly that binds insulin-like growth factors IGF1 or IGF2. This ontology term captures both signaling receptor complexes, such as the insulin-like growth factor 1 receptor (IGF1R) complex, which possesses intrinsic tyrosine kinase activity and initiates intracellular signaling cascades upon ligand binding, and non-signaling receptor complexes such as the insulin-like growth factor 2 receptor (IGF2R), which functions to sequester IGF2 and regulate its bioavailability by directing it to lysosomal degradation. These complexes regulate cell growth, proliferation, survival, and development by modulating IGF signaling. Researchers study GO:0140308 because IGF signaling is a central axis in normal development and in multiple diseases, including cancer, metabolic disorders, and thyroid pathology. The receptor complex is not a single static entity; it integrates ligand availability, receptor isoform composition, and crosstalk with other membrane receptors such as integrins. Understanding its assembly and regulation is therefore essential for interpreting experiments that manipulate IGF pathway genes. The term is also important for annotation and data mining. When RNA-seq, proteomics, or CRISPR screens identify IGF receptor components, mapping them to GO:0140308 provides a standardized way to connect molecular observations to a defined cellular component. This article summarizes the definition, composition, mechanisms, disease links, and research methods relevant to this complex.
insulin-like growth factor binding receptor complex At A Glance
| GO ID | GO:0140308 |
|---|---|
| GO term | insulin-like growth factor binding receptor complex |
| Ontology | cellular_component |
| Synonym | IGF-binding receptor complex |
| Major function | Binds IGF1 or IGF2 at the plasma membrane to modulate IGF signaling, either by initiating intracellular cascades or by sequestering ligand for lysosomal degradation |
| Location | Plasma membrane |
| Ligands | IGF1 and IGF2 |
| Representative components | IGF1R, IGF2R, insulin receptor isoforms, IGF-binding proteins |
| Biological context | Cell growth, proliferation, survival, and development |
What Is GO:0140308?
GO:0140308, insulin-like growth factor binding receptor complex, is defined as a plasma membrane-localized protein complex that binds insulin-like growth factors IGF1 or IGF2. This class includes both signaling receptor complexes, such as the IGF1R complex, which possesses intrinsic tyrosine kinase activity and initiates intracellular signaling cascades upon ligand binding, and non-signaling receptor complexes such as IGF2R, which functions to sequester IGF2 and regulate its bioavailability by directing it to lysosomal degradation. These complexes regulate cell growth, proliferation, survival, and development by modulating IGF signaling.
Why Is insulin-like growth factor binding receptor complex Important in Cell Biology?
GO:0140308 is important because IGF-binding receptor complexes sit at the interface between circulating growth factors and intracellular signaling, controlling fundamental processes such as cell growth, proliferation, survival, and development. Dysregulation of these complexes contributes to cancer progression, metabolic disease, and thyroid disorders, making them attractive targets for mechanistic studies and therapeutic development. Because the complex includes both signaling and non-signaling receptors, it also provides a model for understanding how ligand bioavailability is regulated at the membrane.
• Controls cell growth and proliferation through IGF1R-mediated tyrosine kinase signaling.
• Regulates IGF2 bioavailability via IGF2R-mediated lysosomal targeting.
• Implicated in multiple cancers, including those with IGF pathway activation.
• Linked to metabolic and endocrine disorders such as IGF-I deficiency and thyroid disease.
• Modulated by IGF-binding proteins that influence receptor binding.
• Crosstalks with integrins and other membrane receptors to shape signaling output.
• Serves as a target for CRISPR-based functional genomics and drug discovery.
• Provides a defined cellular component for annotation of proteomic and transcriptomic data.
Structure and Composition of insulin-like growth factor binding receptor complex
Ligand binding at the plasma membrane
In simple terms: The complex sits on the cell surface and grabs IGF1 or IGF2.
The insulin-like growth factor binding receptor complex is plasma membrane-localized and binds IGF1 or IGF2 with high specificity. Ligand binding is the first step that determines whether the complex signals or sequesters the growth factor. IGF2 binding in particular is central to the non-signaling function of IGF2R.
Signaling receptor components: IGF1R and insulin receptor isoforms
In simple terms: Some versions of the complex send signals into the cell after binding IGF.
Signaling receptor complexes such as the IGF1R complex possess intrinsic tyrosine kinase activity and initiate intracellular signaling cascades upon ligand binding. Insulin receptor isoforms and IGF-like receptors also contribute to cell signaling, carcinogenesis, and chemoresistance, and can assemble into related receptor complexes. These components define the signaling arm of GO:0140308.
Non-signaling receptor components: IGF2R
In simple terms: Other versions of the complex act as a sponge that sends IGF2 for destruction.
The insulin-like growth factor 2 receptor (IGF2R) is a non-signaling receptor complex that sequesters IGF2 and regulates its bioavailability by directing it to lysosomal degradation. This function is distinct from tyrosine kinase signaling and highlights the dual nature of GO:0140308.
Modulatory components: IGF-binding proteins
In simple terms: Helper proteins can change how easily IGF reaches the receptor.
IGF-binding proteins modulate IGF activity and receptor binding, thereby influencing the composition and output of IGF-binding receptor complexes. For example, IGFBP-3 has nuclear actions and can affect IGF signaling beyond the membrane. These proteins are not core receptor subunits but are functionally associated with the complex.
Crosstalk with integrins and other membrane receptors
In simple terms: The IGF receptor complex can talk to other surface receptors to change the signal.
Crosstalk between IGF receptor and integrins occurs through direct integrin binding to IGF1, which can modify signaling outcomes. This means the functional assembly of GO:0140308 can include or be influenced by additional membrane proteins, expanding its regulatory potential.
Key Genes Involved in GO:0140308 insulin-like growth factor binding receptor complex
The following genes and proteins are central to the composition, regulation, and function of the insulin-like growth factor binding receptor complex (GO:0140308).
| Gene | Major Role | Research Relevance |
|---|---|---|
| IGF1R | Signaling receptor with intrinsic tyrosine kinase activity that binds IGF1/IGF2 | Target for cancer and growth studies; knockout and point-mutation models |
| IGF2R | Non-signaling receptor that sequesters IGF2 for lysosomal degradation | Key to ligand bioavailability and tumor suppression studies |
| INSR | Insulin receptor isoforms that can form IGF-like receptor complexes | Implicated in cell signaling, carcinogenesis, and chemoresistance |
| IGF1 | Ligand that binds the receptor complex and activates signaling | Central to growth, development, and disease models |
| IGF2 | Ligand that binds IGF1R and IGF2R with distinct outcomes | Regulates proliferation and is sequestered by IGF2R |
| IGFBP1 | IGF-binding protein that modulates ligand availability | Affects receptor binding and metabolic studies |
| IGFBP2 | IGF-binding protein that modulates IGF activity | Used in binding and signaling assays |
| IGFBP3 | IGF-binding protein with nuclear actions and receptor modulation | Studied in growth and cancer contexts |
| IGFBP4 | IGF-binding protein influencing IGF-receptor interaction | Relevant to bioavailability studies |
| IGFBP5 | IGF-binding protein that can affect cell growth | Used in functional assays |
| IGFBP6 | IGF-binding protein modulating IGF signaling | Potential marker in disease models |
| ITGB1 | Integrin subunit that crosstalks with IGF1 | Studied for integrin-IGF crosstalk |
| ITGB3 | Integrin subunit involved in IGF1 binding crosstalk | Relevant to adhesion and signaling studies |
| IRS1 | Downstream substrate of IGF1R signaling | Readout for receptor activation |
| IRS2 | Downstream substrate of IGF1R signaling | Readout for receptor activation |
| AKT1 | Downstream kinase in IGF signaling | Functional readout in knockout and knock-in models |
| MAPK1 | Downstream kinase in IGF signaling | Functional readout in signaling studies |
How Is insulin-like growth factor binding receptor complex Regulated?
The insulin-like growth factor binding receptor complex is regulated at multiple levels. Ligand availability is controlled by IGF-binding proteins, which modulate IGF activity and receptor binding. Receptor abundance and isoform composition, including insulin receptor isoforms and IGF-like receptors, influence signaling output and chemoresistance. Crosstalk with integrins through direct binding to IGF1 provides an additional layer of regulation. At the cellular level, ligand-bound IGF1R initiates intracellular cascades that are subject to feedback and downstream modulation, while IGF2R sequesters IGF2 for lysosomal degradation, effectively reducing ligand bioavailability. These mechanisms together determine whether IGF signaling promotes growth, survival, or is terminated.
insulin-like growth factor binding receptor complex and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| IGF1R | Cancer, chemoresistance | Knockout and point-mutation cell lines |
| IGF2R | Ligand bioavailability, tumor suppression | Knockout and overexpression models |
| INSR | Metabolic disorders, cancer signaling | Isoform-specific knock-in models |
| IGF1 | IGF-I deficiency, growth disorders | Knock-in and overexpression models |
| IGFBP3 | Growth and cancer biology | Overexpression and knockout models |
Cancer and chemoresistance
Dysregulated IGF-binding receptor complexes are implicated in carcinogenesis and chemoresistance. Insulin receptor isoforms and IGF-like receptors have implications in cell signaling, carcinogenesis, and chemoresistance, making them relevant to cancer research. The IGF axis is broadly involved in diseases, and receptor complex components are frequently altered in tumors.
Metabolic and endocrine disorders
IGF-I deficiency is a recognized clinical condition linked to growth and metabolic abnormalities. The IGF pathway also plays a role in thyroid disease, where IGF signaling intersects with thyroid cell growth and function. These disorders highlight the importance of proper IGF-binding receptor complex function.
Growth and developmental disorders
Because the complex regulates cell growth, proliferation, survival, and development, disruptions can lead to developmental abnormalities. IGF2 bioavailability, controlled by IGF2R, is particularly important during development.
From insulin-like growth factor binding receptor complex-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of IGF1R abolish IGF-induced signaling? | IGF1R knockout cell line |
| How does a specific IGF1R mutation affect kinase activity? | Point-mutation knock-in |
| What is the effect of IGF2R sequestration on IGF2 levels? | IGF2R knockout or overexpression |
| Can tagged IGF1R be used to track complex assembly? | Tagged knock-in |
| Does overexpression of IGFBP3 alter receptor binding? | Overexpression cell model |
| Which genes modulate IGF receptor complex function? | CRISPR library screening |
How to Study the insulin-like growth factor binding receptor complex Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA-seq | Transcript abundance of IGF receptor complex genes | Expression profiling after CRISPR perturbation |
| Proteomics | Protein composition and interactions | Identifying complex components |
| Ligand-binding assay | Direct binding of IGF1/IGF2 | Receptor affinity and sequestration studies |
| Western blot | Phosphorylation of downstream targets | Signaling activation readout |
| Immunofluorescence | Plasma membrane localization | Confirming cellular component |
| CRISPR screen | Genes affecting IGF signaling | Functional genomics |
| Co-immunoprecipitation | Protein-protein interactions | Complex assembly studies |
Transcriptomic and proteomic profiling
RNA-seq and proteomics can identify changes in expression of IGF receptor complex components and associated genes after perturbations. These methods help map the functional network around GO:0140308.
Ligand-binding assays
Binding assays using IGF1 or IGF2 measure direct interaction with the receptor complex and are foundational for studying IGF2R sequestration and IGF1R activation.
Signaling readouts
Phosphorylation of downstream substrates such as IRS1, IRS2, AKT1, and MAPK1 serves as a readout of IGF1R complex activity. These assays are used in knockout and knock-in models.
Imaging and localization
Fluorescence imaging of tagged receptors can visualize plasma membrane localization and assembly of the complex. This is useful for confirming the cellular component annotation.
How CRISPR Can Be Used to Study GO:0140308 insulin-like growth factor binding receptor complex
Knockout
CRISPR knockout of IGF1R, IGF2R, or INSR can abolish or alter IGF-binding receptor complex function, enabling causal tests of signaling and ligand sequestration. Knockout models are widely used to study growth, proliferation, and survival phenotypes.
Point Mutation
Point mutations can be introduced into kinase domains or ligand-binding regions of IGF1R or IGF2R to dissect specific residues required for signaling or ligand capture. Such models help distinguish signaling from non-signaling functions.
Knock-in
Knock-in of tagged receptors or disease-associated variants allows tracking of complex localization and function in live cells. This is useful for imaging and interaction studies.
Overexpression
Overexpression of IGF1R, IGF2R, or IGF-binding proteins can model gain-of-function states observed in cancer and other diseases. These models are used to test ligand bioavailability and downstream signaling.
How EDITGENE Supports insulin-like growth factor binding receptor complex Research
Researchers studying insulin-like growth factor binding receptor complex-related genes often need to determine whether a candidate gene is causally involved in receptor assembly, ligand binding, or downstream signaling. EDITGENE provides CRISPR-based cell model services to support these investigations.
Contact EDITGENE today to design your custom CRISPR model for insulin-like growth factor binding receptor complex research.
Frequently Asked Questions About insulin-like growth factor binding receptor complex
What is GO:0140308?
GO:0140308 is the insulin-like growth factor binding receptor complex, a plasma membrane-localized protein complex that binds IGF1 or IGF2 and includes both signaling and non-signaling receptors.
What genes are involved in the insulin-like growth factor binding receptor complex?
Key genes include IGF1R, IGF2R, INSR, IGF1, IGF2, and IGF-binding proteins such as IGFBP3.
What is the function of the IGF-binding receptor complex?
It regulates cell growth, proliferation, survival, and development by modulating IGF signaling, either through tyrosine kinase cascades or by sequestering IGF2 for lysosomal degradation.
How does IGF2R differ from IGF1R in this complex?
IGF1R is a signaling receptor with intrinsic tyrosine kinase activity, while IGF2R is a non-signaling receptor that sequesters IGF2 and directs it to lysosomal degradation.
What diseases are linked to IGF-binding receptor complexes?
They are linked to cancer, chemoresistance, metabolic disorders, IGF-I deficiency, and thyroid disease.
How can CRISPR be used to study GO:0140308?
CRISPR knockout, point mutation, knock-in, and overexpression models can test the causal roles of IGF1R, IGF2R, and other components.
What are the main protein components of the IGF-binding receptor complex?
Main components include IGF1R, IGF2R, insulin receptor isoforms, and modulatory IGF-binding proteins.
Where is the insulin-like growth factor binding receptor complex located?
It is localized to the plasma membrane.
What ligands bind to the IGF-binding receptor complex?
The complex binds IGF1 and IGF2.
How is IGF signaling regulated at the receptor complex level?
It is regulated by ligand availability through IGF-binding proteins, receptor isoform composition, and crosstalk with integrins.
Conclusion
GO:0140308, the insulin-like growth factor binding receptor complex, defines a plasma membrane assembly that binds IGF1 or IGF2 and integrates signaling and ligand sequestration functions. Its components, including IGF1R, IGF2R, and insulin receptor isoforms, are central to growth, proliferation, survival, and disease. Understanding this complex through CRISPR models and functional assays provides a foundation for therapeutic and diagnostic research.
References
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