GO:1903526 negative regulation of membrane tubulation: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:1903526 (negative regulation of membrane tubulation) is a biological process that stops, prevents, or reduces the frequency, rate, or extent of membrane tubulation.
• Membrane tubulation is driven by curvature-generating proteins such as BAR-domain proteins (e.g., PACSIN2, BIN1, endophilin) and is counteracted by factors that alter membrane charge, lipid composition, or protein recruitment.
• Negative regulation can occur through cholesterol depletion, changes in membrane charge, or competition between curvature proteins, as shown for PACSIN2 and BIN1.
• Tetraspanner-based nanodomains and mixtures of curvature proteins modulate BAR domain-induced membrane curvature, providing mechanisms for negative regulation.
• Dysregulation of membrane tubulation is linked to cancer, neurodegeneration, and mitochondrial dynamics disorders.
• CRISPR-based knockout, point mutation, knock-in, and overexpression models are essential to dissect the causal roles of genes in negative regulation of membrane tubulation.
Description
Membrane tubulation is a fundamental cellular process that generates tubular invaginations or protrusions from lipid bilayers, essential for endocytosis, organelle shaping, and vesicular transport. The Gene Ontology term GO:1903526, negative regulation of membrane tubulation, describes any process that stops, prevents, or reduces the frequency, rate, or extent of this tubulation. This regulatory process is critical for maintaining membrane homeostasis and is implicated in diverse physiological and pathological states. Researchers study negative regulation of membrane tubulation to understand how cells control membrane curvature, lipid composition, and protein recruitment, and to identify therapeutic targets for diseases such as cancer and neurodegeneration.
negative regulation of membrane tubulation At A Glance
| GO ID | GO:1903526 |
|---|---|
| GO term | negative regulation of membrane tubulation |
| Ontology | biological_process |
| Synonym | down regulation of membrane tubulation; inhibition of membrane tubulation; negative regulation of plasma membrane tubulation |
| Major function | Stops, prevents, or reduces the frequency, rate, or extent of membrane tubulation |
| Related processes | Membrane curvature, endocytosis, organelle dynamics, vesicular transport |
| Key regulators | PACSIN2, BIN1, endophilin, cholesterol, membrane charge |
| Disease relevance | Cancer, neurodegeneration, mitochondrial disorders |
What Is GO:1903526?
GO:1903526 (negative regulation of membrane tubulation) is defined as any process that stops, prevents, or reduces the frequency, rate, or extent of membrane tubulation. Membrane tubulation itself is the generation of tubular membrane structures, often driven by protein-mediated curvature. Negative regulation therefore encompasses mechanisms that inhibit or reverse this tubulation, such as altering membrane lipid composition, changing membrane charge, or modulating the activity of curvature-generating proteins.
Why Is negative regulation of membrane tubulation Important in Cell Biology?
Negative regulation of membrane tubulation is essential for cellular homeostasis because uncontrolled tubulation can disrupt membrane integrity, organelle function, and vesicular trafficking. Understanding this process provides insights into how cells dynamically remodel membranes and how dysregulation contributes to diseases such as cancer and neurodegeneration. Moreover, it offers potential targets for therapeutic intervention, as modulating tubulation can affect endocytic pathways and organelle dynamics.
• Controls membrane homeostasis and prevents aberrant tubulation.
• Regulates endocytosis and vesicular transport.
• Influences organelle shape and function, including mitochondria.
• Modulates cell signaling by affecting membrane receptor clustering.
• Implicated in cancer progression through altered membrane dynamics.
• Linked to neurodegeneration via defects in membrane trafficking.
• Provides targets for antiviral and anticancer therapies.
• Essential for understanding lipid-protein interactions in membranes.
• Helps explain how cells adapt to changes in membrane charge and lipid composition.
• Enables development of CRISPR-based models to study disease mechanisms.
What Happens During negative regulation of membrane tubulation?
Initiation of negative regulation
In simple terms: The cell senses excessive tubulation and starts to counteract it.
Negative regulation of membrane tubulation can be initiated by changes in membrane lipid composition, such as cholesterol depletion, which alters membrane fluidity and curvature. Additionally, changes in membrane charge can recruit or repel curvature-generating proteins, thereby inhibiting tubulation.
Modulation of curvature-generating proteins
In simple terms: Proteins that bend membranes are stopped or slowed down.
Curvature-generating proteins such as PACSIN2 and BIN1 are key drivers of tubulation. Their activity can be negatively regulated by altering membrane charge, as shown for BIN1 where increased membrane charge reduces tubulation. Similarly, PACSIN2-mediated tubulation is inhibited by cholesterol depletion. Mixtures of multiple curvature proteins can also modulate each other's activity, leading to reduced tubulation.
Role of tetraspanner-based nanodomains
In simple terms: Special protein clusters in the membrane can block tubulation.
Tetraspanner-based nanodomains, such as those formed by tetraspanins, can modulate BAR domain-induced membrane curvature. These nanodomains act as platforms that reorganize membrane lipids and proteins, thereby negatively regulating tubulation.
Coincidence detection and lipid charge
In simple terms: Proteins need multiple signals to bend membranes; blocking one stops tubulation.
Endophilin recruitment and subsequent membrane curvature generation require coincidence detection of GPCR loop interactions and negative lipid charge. Disrupting either signal reduces tubulation, providing a mechanism for negative regulation.
Mitochondrial tubulation vs. fragmentation
In simple terms: In mitochondria, negative regulation of tubulation promotes fragmentation.
Mitochondrial fusion involves tubulation, while fragmentation is the opposite. Negative regulation of membrane tubulation in mitochondria can shift the balance toward fragmentation, as reviewed in the context of mitochondrial dynamics.
Key Genes Involved in GO:1903526 negative regulation of membrane tubulation
The following genes and proteins are key players in negative regulation of membrane tubulation, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| PACSIN2 | BAR-domain protein involved in tubulation; its activity is inhibited by cholesterol depletion | Studying cholesterol-dependent regulation of tubulation |
| BIN1 | BAR-domain protein that tubulates membranes; regulated by membrane charge | Target for cancer and neurodegeneration research |
| Endophilin | Curvature-generating protein requiring GPCR and lipid charge for recruitment | Understanding coincidence detection in membrane curvature |
| C8 peptide | Anti-FIV peptide that binds charged membranes and affects tubulation | Antiviral research and membrane model studies |
| Tetraspanins | Form nanodomains that modulate BAR domain-induced curvature | Investigating membrane organization and curvature |
| I-BAR domains | Proteins that induce negative curvature; their regulation affects tubulation | Biophysical studies of membrane shape transitions |
| Multiple curvature proteins | Mixtures can modulate each other's tubulation activity | Computational and theoretical membrane remodeling |
| Mitochondrial fusion proteins | Mediate tubulation; their negative regulation leads to fragmentation | Mitochondrial dynamics and disease |
| GPCRs | Interact with endophilin to promote curvature; blocking interaction inhibits tubulation | Signaling and membrane trafficking |
| Cholesterol | Lipid that affects membrane fluidity and tubulation; depletion inhibits PACSIN2-mediated tubulation | Lipid raft and membrane dynamics research |
| Phosphoinositides | Lipids that recruit curvature proteins; their levels affect tubulation | Membrane charge and signaling studies |
| FIV (feline immunodeficiency virus) | Virus whose peptide C8 affects membrane tubulation | Antiviral peptide development |
| BAR domain proteins | Family of curvature-sensing/generating proteins | Structural and biophysical studies |
| PACSIN2 mutants | Altered tubulation activity | CRISPR knock-in models for cholesterol regulation |
| BIN1 mutants | Charge-sensitive tubulation defects | Disease modeling in cancer and neurodegeneration |
| Endophilin mutants | Defective coincidence detection | Point mutation studies for lipid binding |
| Tetraspanin mutants | Disrupted nanodomain formation | Knockout models for membrane organization |
How Is negative regulation of membrane tubulation Regulated?
Negative regulation of membrane tubulation is controlled by multiple factors. Cholesterol depletion inhibits PACSIN2-mediated tubulation. Membrane charge alterations reduce BIN1-mediated tubulation. Coincidence detection of GPCR loop interactions and negative lipid charge regulates endophilin recruitment. Tetraspanner-based nanodomains modulate BAR domain-induced curvature. Mixtures of curvature proteins can also mutually regulate their activities. These mechanisms ensure tight control of membrane dynamics.
negative regulation of membrane tubulation and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| BIN1 | Cancer, Alzheimer's disease | Knockout and point mutation in cancer cell lines |
| PACSIN2 | Membrane trafficking disorders | Cholesterol-dependent tubulation assays |
| Endophilin | Neurodegeneration, signaling | Coincidence detection mutants |
| Tetraspanins | Cancer, immune disorders | Nanodomain disruption models |
| Mitochondrial fusion proteins | Mitochondrial myopathies | Fragmentation/tubulation balance studies |
Cancer
Altered membrane tubulation and its negative regulation are implicated in cancer. BIN1, a tumor suppressor, mediates membrane tubulation, and its regulation by membrane charge affects cancer cell behavior. Dysregulation of endocytic pathways involving tubulation can promote tumor progression.
Neurodegeneration
Defects in membrane tubulation contribute to neurodegenerative diseases. BIN1 is a risk factor for Alzheimer's disease, and its role in membrane curvature is critical for neuronal function. Mitochondrial dynamics, including tubulation and fragmentation, are linked to neurodegeneration.
Viral infections
Membrane tubulation is exploited by viruses for entry and replication. The anti-FIV peptide C8 binds charged membranes and affects tubulation, suggesting therapeutic potential.
From negative regulation of membrane tubulation-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does PACSIN2 regulate tubulation via cholesterol? | PACSIN2 knockout cells with cholesterol depletion |
| How does membrane charge affect BIN1 tubulation? | BIN1 point mutants in charged lipid environments |
| What is the role of endophilin coincidence detection? | Endophilin knock-in with mutated GPCR binding site |
| Do tetraspanin nanodomains modulate BAR proteins? | Tetraspanin overexpression and knockout |
| How do multiple curvature proteins interact? | Co-expression of BAR proteins in model membranes |
| What is the impact of mitochondrial tubulation on disease? | Knockout of fusion proteins in neuronal cells |
How to Study the negative regulation of membrane tubulation Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell imaging | Tubulation dynamics and protein localization | Real-time regulation studies |
| Liposome assays | Membrane curvature and protein binding | In vitro reconstitution |
| Atomic force microscopy | Membrane morphology and elasticity | Biophysical characterization |
| Electron microscopy | Ultrastructure of tubules | High-resolution imaging |
| CRISPR knockout screening | Gene function in tubulation | Identifying negative regulators |
| RNA-seq | Transcriptional changes | Pathway analysis |
| Proteomics | Protein interactions and modifications | Identifying complexes |
Live-cell imaging
Live-cell fluorescence microscopy allows real-time visualization of membrane tubulation and its negative regulation. Using fluorescently tagged curvature proteins (e.g., PACSIN2, BIN1) and membrane dyes, researchers can quantify tubulation dynamics.
In vitro membrane models
Liposome-based assays and supported lipid bilayers reconstitute tubulation with purified proteins. These models help dissect the effects of lipid composition, charge, and protein mixtures on tubulation.
Biophysical techniques
Techniques such as atomic force microscopy, electron microscopy, and fluorescence correlation spectroscopy measure membrane curvature and protein binding. They provide quantitative insights into negative regulation mechanisms.
CRISPR screening
Genome-wide CRISPR knockout screens can identify genes that negatively regulate membrane tubulation. Coupled with imaging-based readouts, this approach uncovers novel regulators.
How CRISPR Can Be Used to Study GO:1903526 negative regulation of membrane tubulation
Knockout
CRISPR knockout of genes such as PACSIN2 or BIN1 can abolish their tubulation activity, revealing their role in negative regulation. Knockout cells show altered membrane dynamics and can be used to test rescue by wild-type or mutant proteins.
Point Mutation
Point mutations in BAR domain proteins (e.g., BIN1, endophilin) can disrupt lipid binding or charge sensing, leading to loss of negative regulation. These models help map functional domains.
Knock-in
Knock-in of tagged or mutant versions of tubulation regulators allows precise tracking and functional analysis. For example, fluorescently tagged PACSIN2 knock-in enables live imaging of tubulation.
Overexpression
Overexpression of negative regulators can suppress tubulation, while overexpression of curvature proteins can enhance it. This approach tests sufficiency and dominance.
How EDITGENE Supports negative regulation of membrane tubulation Research
Researchers studying negative regulation of membrane tubulation-related genes often need to determine whether a candidate gene is causally involved in the process or is merely correlated. EDITGENE provides CRISPR-based services to create knockout, point mutation, knock-in, and overexpression cell models, enabling functional validation and mechanistic studies.
Contact EDITGENE today to design your custom CRISPR model for negative regulation of membrane tubulation research.
Frequently Asked Questions About negative regulation of membrane tubulation
What is GO:1903526?
GO:1903526 is the Gene Ontology term for negative regulation of membrane tubulation, a biological process that stops, prevents, or reduces the frequency, rate, or extent of membrane tubulation.
What genes are involved in negative regulation of membrane tubulation?
Key genes include PACSIN2, BIN1, endophilin, and tetraspanins, which modulate membrane curvature and tubulation.
How is membrane tubulation negatively regulated?
It can be negatively regulated by cholesterol depletion, changes in membrane charge, tetraspanner nanodomains, and coincidence detection mechanisms.
What diseases are linked to negative regulation of membrane tubulation?
Dysregulation is linked to cancer, neurodegeneration, and viral infections.
What methods study negative regulation of membrane tubulation?
Live-cell imaging, liposome assays, biophysical techniques, and CRISPR screening are commonly used.
What is the role of PACSIN2 in membrane tubulation?
PACSIN2 is a BAR-domain protein that induces tubulation, which is inhibited by cholesterol depletion.
How does BIN1 regulate membrane tubulation?
BIN1 mediates tubulation, and its activity is regulated by membrane charge; increased charge reduces tubulation.
What are tetraspanner-based nanodomains?
They are membrane domains formed by tetraspanins that modulate BAR domain-induced curvature, contributing to negative regulation.
Can CRISPR be used to study negative regulation of membrane tubulation?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models enable functional studies of genes involved.
What is the significance of negative regulation of membrane tubulation in mitochondria?
It balances mitochondrial fusion and fragmentation; dysregulation leads to mitochondrial disorders.
Conclusion
Negative regulation of membrane tubulation (GO:1903526) is a critical biological process that controls membrane dynamics and prevents aberrant tubulation. Key regulators such as PACSIN2, BIN1, and endophilin are modulated by lipid composition, membrane charge, and protein-protein interactions. Dysregulation of this process is implicated in cancer, neurodegeneration, and viral infections. CRISPR-based models and advanced imaging techniques are essential to dissect these mechanisms and identify therapeutic targets.
References
- 1. Gusmira A et al.. 2020. Regulation of caveolae through cholesterol-depletion-dependent tubulation mediated by PACSIN2.. J Cell Sci 133(19) PMID: 32878944
- 2. Chen Z et al.. 2015. Regulation of membrane-shape transitions induced by I-BAR domains.. Biophys J 109(2):298-307 PMID: 26200865
- 3. Kumar G et al.. 2022. Membrane Remodeling Due to a Mixture of Multiple Types of Curvature Proteins.. J Chem Theory Comput 18(9):5659-5671 PMID: 35981766
- 4. Haase D et al.. 2023. Tetraspanner-based nanodomains modulate BAR domain-induced membrane curvature.. EMBO Rep 24(12):e57232 PMID: 37902009
- 5. Gowrisankaran S et al.. 2020. Cells Control BIN1-Mediated Membrane Tubulation by Altering the Membrane Charge.. J Mol Biol 432(4):1235-1250 PMID: 31857086
- 6. Mondal S et al.. 2021. Endophilin recruitment drives membrane curvature generation through coincidence detection of GPCR loop interactions and negative lipid charge.. J Biol Chem 296:100140 PMID: 33268381
- 7. Di Marino D et al.. 2020. Binding of the Anti-FIV Peptide C8 to Differently Charged Membrane Models: From First Docking to Membrane Tubulation.. Front Chem 8:493 PMID: 32676493
- 8. Escobar-Henriques M et al.. 2013. Mechanistic perspective of mitochondrial fusion: tubulation vs. fragmentation.. Biochim Biophys Acta 1833(1):162-75 PMID: 22884630
