GO:0060244 negative regulation of cell proliferation involved in contact inhibition: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0060244 describes the biological process that stops or reduces cell proliferation when cells become densely packed, a phenomenon known as contact inhibition.
• Key molecular players include cell adhesion molecules such as E-cadherin and VE-cadherin, the Hippo pathway effector YAP/TAZ, and the transcription factor Hes1.
• Loss of contact inhibition is a hallmark of cancer, contributing to uncontrolled proliferation and tumor growth.
• Contact inhibition is regulated by signaling pathways involving p38 MAPK, NF2/Merlin, and Csk, which modulate proliferation in response to cell density.
• Experimental models for studying GO:0060244 include knockout, point mutation, knock-in, and overexpression cell lines, as well as CRISPR library screening.
• Understanding this process provides insights into tissue homeostasis, development, and cancer pathogenesis.
Description
Contact inhibition is a fundamental biological process that ensures cells stop dividing when they become crowded, maintaining tissue architecture and preventing uncontrolled growth. The Gene Ontology term GO:0060244, negative regulation of cell proliferation involved in contact inhibition, captures the signaling events that halt proliferation in response to increasing cell density. This process is critical for normal development and tissue homeostasis, and its dysregulation is a key feature of many cancers. Researchers study GO:0060244 to understand how cells sense density and how this sensing is bypassed in disease. Key molecules such as E-cadherin, VE-cadherin, and Hes1 have been shown to mediate contact inhibition in various cell types. This article synthesizes current knowledge on the mechanisms, genes, and research methods associated with GO:0060244, providing a resource for biomedical researchers.
negative regulation of cell proliferation involved in contact inhibition At A Glance
| GO ID | GO:0060244 |
|---|---|
| GO term | negative regulation of cell proliferation involved in contact inhibition |
| Ontology | biological_process |
| Synonym | none |
| Major function | Stops or reduces cell proliferation in response to cell density |
| Related processes | Contact inhibition, cell density sensing, growth arrest |
| Key regulators | E-cadherin, VE-cadherin, Hes1, NF2/Merlin, p38 MAPK |
| Disease relevance | Cancer, tissue overgrowth, developmental disorders |
What Is GO:0060244?
GO:0060244 is defined as any process that stops, prevents, or reduces the rate or extent of cell proliferation in response to cell density. In simpler terms, it is the mechanism by which cells sense that they are becoming too crowded and consequently slow down or stop dividing. This process is a specific aspect of contact inhibition, distinct from other forms of growth arrest.
Why Is negative regulation of cell proliferation involved in contact inhibition Important in Cell Biology?
GO:0060244 is essential for maintaining tissue homeostasis and preventing tumorigenesis. Loss of contact inhibition allows cells to proliferate beyond normal limits, a hallmark of cancer. Understanding the molecular mechanisms of this process can reveal therapeutic targets and biomarkers for cancer and other proliferative diseases. Moreover, contact inhibition plays roles in development, wound healing, and stem cell regulation.
• Prevents uncontrolled cell proliferation in normal tissues.
• Its dysregulation is a key step in cancer development.
• Involved in tissue patterning during development.
• Regulates stem cell quiescence and activation.
• Mediates density-dependent inhibition in various cell types, including fibroblasts, Schwann cells, and epithelial cells.
• Provides a model for studying cell-cell communication and signaling.
• Potential target for anti-cancer therapies aimed at restoring contact inhibition.
• Relevant to regenerative medicine and tissue engineering.
• Helps understand how cells integrate adhesion and growth signals.
• Contributes to the maintenance of organ size and architecture.
What Happens During negative regulation of cell proliferation involved in contact inhibition?
Cell density sensing and adhesion
In simple terms: Cells sense when they are touching too many neighbors.
As cells proliferate and become densely packed, cell-cell adhesion molecules such as E-cadherin and VE-cadherin engage in homophilic interactions, triggering intracellular signals that inhibit proliferation. This adhesion-dependent signaling is a prerequisite for contact inhibition. For example, dominant-negative E-cadherin reverses contact inhibition in breast carcinoma cells, highlighting its essential role.
Activation of Hippo pathway and YAP/TAZ regulation
In simple terms: A signaling pathway called Hippo gets turned on and stops growth-promoting proteins.
Cell contact and the tumor suppressor NF2/Merlin regulate the Hippo pathway, leading to phosphorylation and inactivation of YAP/TAZ, which are transcriptional co-activators that promote proliferation. This inactivation reduces the expression of growth-promoting genes, contributing to contact inhibition. TEAD palmitoylation is also regulated by cell contact and NF2/Merlin, affecting YAP/TAZ activity.
Transcriptional regulation by Hes1 and other factors
In simple terms: Certain transcription factors change gene expression to stop cell division.
Hes1 is required for contact inhibition of cell proliferation in 3T3-L1 preadipocytes. Its expression or activity may be modulated by cell density, leading to altered expression of target genes that control the cell cycle. Other transcription factors, such as those downstream of p38 MAPK, may also contribute.
Inhibition of proliferative signaling pathways
In simple terms: Growth-promoting signals are blocked when cells are crowded.
Contact inhibition involves attenuation of mitogenic signaling. For instance, p38 MAPK activity is attenuated upon contact inhibition in fibroblasts. Additionally, Csk associated with VE-cadherin inhibits cell proliferation by phosphorylating Src family kinases and reducing their activity. These events collectively reduce the drive to proliferate.
Cell cycle arrest
In simple terms: The cell cycle machinery is halted, so cells stop dividing.
Ultimately, contact inhibition leads to cell cycle arrest, often in G1 phase. This involves downregulation of cyclins and CDKs, and upregulation of CDK inhibitors. While specific mechanisms may vary by cell type, the integration of adhesion, Hippo, and other signals converges on the cell cycle machinery to enforce quiescence.
Key Genes Involved in GO:0060244 negative regulation of cell proliferation involved in contact inhibition
The following genes and proteins have been experimentally implicated in the regulation of contact inhibition of cell proliferation.
| Gene | Major Role | Research Relevance |
|---|---|---|
| CDH1 (E-cadherin) | Cell-cell adhesion; mediates contact inhibition | Loss reverses contact inhibition in breast cancer |
| CDH5 (VE-cadherin) | Endothelial cell adhesion; recruits Csk to inhibit proliferation | Regulates endothelial contact inhibition |
| HES1 | Transcription factor; required for contact inhibition in preadipocytes | Knockdown abolishes contact inhibition |
| NF2 (Merlin) | Tumor suppressor; regulates Hippo pathway and TEAD palmitoylation | Mutations cause neurofibromatosis type 2 |
| YAP1 | Transcriptional co-activator; promotes proliferation | Inactivated by contact inhibition |
| WWTR1 (TAZ) | Transcriptional co-activator; promotes proliferation | Inactivated by contact inhibition |
| TEAD1-4 | Transcription factors; mediate YAP/TAZ effects | Palmitoylation regulated by cell contact |
| CSK | Tyrosine kinase; inhibits Src family kinases | Associated with VE-cadherin to inhibit proliferation |
| SRC | Proto-oncogene; promotes proliferation | Inhibited by Csk upon contact |
| MAPK14 (p38α) | Stress-activated kinase; attenuates proliferation | Activity reduced upon contact inhibition |
| CDKN1A (p21) | CDK inhibitor; induces cell cycle arrest | Potential mediator of contact inhibition |
| CDKN1B (p27) | CDK inhibitor; induces cell cycle arrest | Potential mediator of contact inhibition |
| CCND1 (Cyclin D1) | Cell cycle regulator; promotes G1/S transition | Downregulated during contact inhibition |
| MYC | Transcription factor; promotes proliferation | Downregulated during contact inhibition |
| SPRED1/2 | Inhibitors of Ras/MAPK pathway | Involved in contact dermatitis model |
| SPRY1/2 | Inhibitors of Ras/MAPK pathway | Involved in contact dermatitis model |
| IL10 | Anti-inflammatory cytokine; inhibits T-cell proliferation | Mediates contact-dependent inhibition |
| TGFB1 | Growth factor; inhibits T-cell proliferation | Mediates contact-dependent inhibition |
How Is negative regulation of cell proliferation involved in contact inhibition Regulated?
The process of contact inhibition is regulated by multiple signaling pathways. The Hippo pathway, via NF2/Merlin, plays a central role by integrating cell density signals to phosphorylate and inactivate YAP/TAZ. Adhesion molecules such as E-cadherin and VE-cadherin recruit signaling components like Csk to inhibit Src family kinases. Additionally, p38 MAPK activity is attenuated upon contact inhibition, reducing proliferative signaling. Transcriptional regulators like Hes1 are required for contact inhibition in certain cell types. In immune cells, contact with mesenchymal stem cells induces IL-10 and TGF-beta, which inhibit T-lymphocyte proliferation. These pathways collectively ensure that proliferation is halted when cells become crowded.
negative regulation of cell proliferation involved in contact inhibition and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| CDH1 | Breast carcinoma, loss of contact inhibition | Knockout or dominant-negative overexpression in breast cancer cell lines |
| NF2 | Neurofibromatosis type 2, meningioma | Knockout in Schwann cells or fibroblasts |
| HES1 | Developmental defects, impaired adipogenesis | Knockout in 3T3-L1 preadipocytes |
| CSK | Endothelial dysfunction, vascular disorders | Knockout or knockdown in endothelial cells |
| IL10/TGFB1 | Autoimmune diseases, impaired immune regulation | Co-culture models with mesenchymal stem cells and T cells |
Cancer
Loss of contact inhibition is a hallmark of cancer. For example, dominant-negative E-cadherin reverses contact inhibition in breast carcinoma cells, leading to uncontrolled proliferation. Mutations in NF2, which regulates the Hippo pathway, cause neurofibromatosis type 2 and predispose to tumors. Understanding how cancer cells bypass contact inhibition can inform targeted therapies.
Developmental disorders
Contact inhibition is crucial for proper tissue patterning during development. Disruption of genes involved, such as Hes1, can lead to developmental abnormalities. However, specific human developmental disorders linked to GO:0060244 are not well-defined in the cited literature.
Inflammatory diseases
Contact-dependent inhibition of T-lymphocyte proliferation by mesenchymal stem cells involves IL-10 and TGF-beta. Dysregulation of this process may contribute to autoimmune diseases or chronic inflammation.
From negative regulation of cell proliferation involved in contact inhibition-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X mediate contact inhibition? | Knockout cell line (e.g., CRISPR-Cas9) |
| Does a specific mutation in gene X affect contact inhibition? | Point mutation knock-in cell line |
| Does tagging gene X with a fluorescent protein affect its function? | Knock-in of tagged gene |
| Does overexpression of gene X enhance contact inhibition? | Overexpression cell line |
| Which genes are essential for contact inhibition? | CRISPR library screening |
| How does gene X contribute to cancer cell proliferation? | Xenograft models with knockout/overexpression |
How to Study the negative regulation of cell proliferation involved in contact inhibition Process
| Method | What It Measures | Typical Application |
|---|---|---|
| BrdU/EdU incorporation | DNA synthesis | Proliferation rate at different densities |
| MTT assay | Metabolic activity | Cell viability and proliferation |
| Western blot | Protein expression and phosphorylation | YAP/TAZ inactivation |
| Immunoprecipitation | Protein-protein interactions | Csk-VE-cadherin association |
| siRNA/CRISPR knockout | Gene function | Testing requirement of Hes1 |
| CRISPR library screen | Identify essential genes | Discovering novel contact inhibition regulators |
| Live-cell imaging | Cell behavior over time | Visualizing density-dependent arrest |
| RNA-seq | Transcriptional changes | Gene expression upon contact inhibition |
Cell proliferation assays
Proliferation can be measured by BrdU incorporation, EdU staining, or MTT assays. These methods quantify DNA synthesis or metabolic activity and are used to assess contact inhibition in response to cell density.
Western blotting and immunoprecipitation
Protein expression and phosphorylation status of key regulators (e.g., YAP/TAZ, p38 MAPK, Src) can be analyzed by Western blotting. Immunoprecipitation can reveal interactions, such as Csk with VE-cadherin.
RNA interference and CRISPR screens
Knockdown or knockout of candidate genes using siRNA or CRISPR-Cas9 allows functional testing. CRISPR library screening can identify novel regulators of contact inhibition.
Live-cell imaging
Time-lapse microscopy can visualize cell proliferation and density over time, providing dynamic insights into contact inhibition.
How CRISPR Can Be Used to Study GO:0060244 negative regulation of cell proliferation involved in contact inhibition
Knockout
CRISPR-Cas9 knockout of genes such as CDH1, HES1, or NF2 can abolish contact inhibition, demonstrating their essential roles. Knockout cell lines are valuable for studying loss-of-function phenotypes.
Point Mutation
Introducing specific point mutations (e.g., in NF2 or CSK) can mimic disease-associated variants and reveal their impact on contact inhibition. This approach helps dissect molecular mechanisms.
Knock-in
Knock-in of tagged versions (e.g., GFP) of genes like VE-cadherin allows real-time visualization of protein localization and dynamics during contact inhibition.
Overexpression
Overexpression of genes such as E-cadherin or Hes1 can enhance contact inhibition, providing gain-of-function insights. This is useful for validating sufficiency.
How EDITGENE Supports negative regulation of cell proliferation involved in contact inhibition Research
Researchers studying negative regulation of cell proliferation involved in contact inhibition-related genes often need to determine whether a candidate gene is causally involved in the process. This requires precise genetic manipulation, which can be achieved through CRISPR-based knockout, point mutation, knock-in, or overexpression models. EDITGENE provides comprehensive services to support such studies.
Contact EDITGENE today to design your custom CRISPR model for negative regulation of cell proliferation involved in contact inhibition research.
Frequently Asked Questions About negative regulation of cell proliferation involved in contact inhibition
What is GO:0060244?
GO:0060244 is the Gene Ontology term for negative regulation of cell proliferation involved in contact inhibition, a process where cells stop dividing when they become densely packed.
What genes are involved in contact inhibition?
Key genes include CDH1 (E-cadherin), CDH5 (VE-cadherin), HES1, NF2, YAP1, and CSK, among others.
How is contact inhibition studied?
Common methods include proliferation assays, Western blotting, CRISPR knockout, and live-cell imaging.
Why is contact inhibition important in cancer?
Loss of contact inhibition allows cancer cells to proliferate uncontrollably, contributing to tumor growth.
What is the role of E-cadherin in contact inhibition?
E-cadherin mediates cell-cell adhesion and is required for contact inhibition; its loss reverses the process in breast cancer cells.
How does the Hippo pathway regulate contact inhibition?
The Hippo pathway, via NF2/Merlin, phosphorylates and inactivates YAP/TAZ upon cell contact, inhibiting proliferation.
What is the role of Hes1 in contact inhibition?
Hes1 is required for contact inhibition in 3T3-L1 preadipocytes; its knockdown abolishes the process.
Can CRISPR be used to study contact inhibition?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to dissect gene function in contact inhibition.
What diseases are linked to defective contact inhibition?
Cancer, particularly breast carcinoma and neurofibromatosis type 2, as well as inflammatory conditions.
How does cell density trigger contact inhibition?
Cell density increases cell-cell adhesion, activating signaling pathways like Hippo and inhibiting proliferative signals.
Conclusion
GO:0060244, negative regulation of cell proliferation involved in contact inhibition, is a critical biological process that maintains tissue homeostasis by halting cell division in response to crowding. Its dysregulation is central to cancer and other proliferative disorders. Key molecular players include adhesion molecules, the Hippo pathway, and transcription factors such as Hes1. Advanced CRISPR-based models and screening approaches are essential for unraveling the mechanisms and identifying therapeutic targets. EDITGENE provides comprehensive services to support such research, from knockout and knock-in models to library screening and bioinformatics.
References
- 1. Sakai H et al.. 2022. Inhibition of Spred/Sprouty Expression in the Skin of a Contact Dermatitis-Like Model.. Biol Pharm Bull 45(8):1208-1212 PMID: 35908904
- 2. Kim NG et al.. 2019. Cell contact and Nf2/Merlin-dependent regulation of TEAD palmitoylation and activity.. Proc Natl Acad Sci U S A 116(20):9877-9882 PMID: 31043565
- 3. Noda N et al.. 2011. Hes1 is required for contact inhibition of cell proliferation in 3T3-L1 preadipocytes.. Genes Cells 16(6):704-13 PMID: 21481105
- 4. Casella GT et al.. 2000. Density dependent regulation of human Schwann cell proliferation.. Glia 30(2):165-77 PMID: 10719358
- 5. Vizirianakis IS et al.. 2002. Dominant-negative E-cadherin alters adhesion and reverses contact inhibition of growth in breast carcinoma cells.. Int J Oncol 21(1):135-44 PMID: 12063560
- 6. Nasef A et al.. 2007. Identification of IL-10 and TGF-beta transcripts involved in the inhibition of T-lymphocyte proliferation during cell contact with human mesenchymal stem cells.. Gene Expr 13(4-5):217-26 PMID: 17605296
- 7. Slisz M et al.. 2008. Attenuation of p38 MAPK activity upon contact inhibition in fibroblasts.. Mol Cell Biochem 308(1-2):65-73 PMID: 17906919
- 8. Baumeister U et al.. 2005. Association of Csk to VE-cadherin and inhibition of cell proliferation.. EMBO J 24(9):1686-95 PMID: 15861137
