GO:0010324 membrane invagination: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0010324 membrane invagination is defined as the infolding of a membrane, a fundamental biological process that shapes cellular membranes during endocytosis, organelle biogenesis, and tissue morphogenesis [1, 2, 3].
• Membrane invagination is driven by BAR domain proteins, dynamins, TMEM16F, and Atg8-family proteins that sense curvature, generate force, and regulate lipid dynamics [1, 2, 4].
• Vacuolar membrane invaginations depend on physicochemical properties of the membrane and cellular factors, including Atg8 and lipid composition [2, 5].
• Podosome formation promotes plasma membrane invagination and integrin-beta3 endocytosis, linking the process to cell adhesion and matrix remodeling.
• Defects in membrane invagination contribute to pathophysiological conditions such as caveolar dysfunction, lysosomal storage disorders, and cancer progression [1, 8].
• CRISPR-based knockout, point mutation, knock-in, and overexpression models enable causal dissection of genes controlling membrane invagination [1, 2, 4].
Description
Membrane invagination (GO:0010324) is a conserved biological process defined as the infolding of a membrane. This process is essential for diverse cellular functions, including endocytosis, vesicle formation, organelle biogenesis, and the generation of membrane reservoirs [1, 3, 4]. Researchers study membrane invagination to understand how cells internalize nutrients, recycle receptors, and respond to mechanical stress [3, 4]. The process is driven by specialized proteins that sense and generate membrane curvature, such as BAR domain proteins and dynamins [1, 4]. In addition, vacuolar membrane invaginations are regulated by Atg8 and the physicochemical properties of the membrane [2, 5]. Membrane invagination also plays a role in tissue morphogenesis, as seen in the formation of rosette structures in the zona glomerulosa. Clinically, defects in membrane invagination are linked to diseases ranging from lysosomal disorders to cancer [1, 8]. This article provides a research-grade overview of GO:0010324, covering its mechanism, key genes, disease relevance, and experimental methods for investigation.
membrane invagination At A Glance
| GO ID | GO:0010324 |
|---|---|
| GO term | membrane invagination |
| Ontology | biological_process |
| Synonym | single-organism membrane invagination |
| Major function | Infolding of a membrane to generate curvature and invaginations |
| Related cellular components | Plasma membrane, vacuolar membrane, caveolae, endosomes |
| Key molecular players | BAR domain proteins, dynamins, TMEM16F, Atg8 |
| Associated processes | Endocytosis, autophagy, organelle biogenesis, cell adhesion |
What Is GO:0010324?
According to the Gene Ontology, GO:0010324 membrane invagination is the biological process defined as the infolding of a membrane. This definition encompasses any inward folding of a cellular membrane, including the plasma membrane, vacuolar membrane, and organellar membranes. The synonym single-organism membrane invagination is also used. This process is distinct from membrane budding or tubulation, although it often precedes or accompanies these events. Membrane invagination is a fundamental mechanism by which cells deform their membranes to create curvature, invaginations, and internal compartments.
Why Is membrane invagination Important in Cell Biology?
Membrane invagination is critical for numerous cellular processes, including nutrient uptake, receptor downregulation, and organelle maintenance [1, 3, 4]. It enables cells to respond to mechanical stress by creating membrane reservoirs, as shown for TMEM16F and dynamins. In autophagy, vacuolar membrane invagination is required for the formation of autophagic bodies and cargo degradation [2, 5]. The process also contributes to tissue architecture, such as rosette formation in the adrenal zona glomerulosa. Dysregulation of membrane invagination is associated with diseases including lysosomal storage disorders, cancer, and caveolar pathologies [1, 8]. Therefore, understanding the molecular mechanisms of GO:0010324 is essential for both basic cell biology and translational research.
• Essential for endocytosis and receptor internalization.
• Required for autophagic vacuole formation and cargo degradation [2, 5].
• Maintains plasma membrane reservoirs under mechanical stress.
• Contributes to cell adhesion and integrin-beta3 endocytosis via podosomes.
• Involved in tissue morphogenesis, including zona glomerulosa rosettes.
• Dysregulated in caveolar invagination-related pathophysiological conditions.
• Linked to lysosomal membrane recycling and dysfunction.
• Provides targets for CRISPR-based functional studies [1, 2, 4].
What Happens During membrane invagination?
Initiation and curvature sensing
In simple terms: The membrane starts to bend inward, and specialized proteins recognize the curve.
Membrane invagination begins with the recruitment of curvature-sensing proteins, such as BAR domain proteins, to specific membrane sites. These proteins detect and stabilize initial membrane curvature, facilitating the infolding process. In caveolar invagination, BAR domain proteins play a central role in shaping the caveolar membrane. Similarly, Atg8 is involved in the regulation of vacuolar membrane invagination, likely by organizing lipid and protein components.
Force generation and membrane remodeling
In simple terms: Molecular machines pull or push the membrane to deepen the invagination.
Dynamins and TMEM16F are key players in generating force for membrane invagination and reservoir formation. Dynamin GTPases constrict membranes, while TMEM16F, a lipid scramblase, alters lipid distribution to promote expansive plasma membrane reservoirs. Podosome formation also promotes plasma membrane invagination and integrin-beta3 endocytosis on viscous RGD-membranes. These mechanical and lipid-driven processes cooperate to deepen the invagination.
Vacuolar membrane invagination
In simple terms: Inside the cell, the vacuolar membrane folds inward to form internal structures.
Vacuolar membrane invagination is regulated by Atg8 and depends on the physicochemical properties of the vacuolar membrane and cellular factors [2, 5]. Kimura et al. showed that membrane lipid composition and cellular factors determine the formation of vacuolar invaginations. This process is essential for autophagy and vacuolar function.
Membrane recycling and lysosomal dynamics
In simple terms: Invaginated membranes can be recycled back to the cell surface or delivered to lysosomes.
Membrane invagination is linked to lysosomal membrane recycling, as hypothesized by Dean, who proposed that lysosomes participate in membrane recycling through invagination and vesicle formation. This recycling is crucial for maintaining membrane homeostasis and responding to cellular demands.
Key Genes Involved in GO:0010324 membrane invagination
The following genes and proteins are experimentally implicated in membrane invagination (GO:0010324) based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| BAR domain proteins (e.g., BIN1, SNX9) | Membrane curvature sensing and stabilization | Caveolar invagination and pathophysiological consequences |
| DNM1, DNM2 (dynamins) | Membrane constriction and force generation | Control of expansive plasma membrane reservoirs |
| TMEM16F (ANO6) | Lipid scrambling and membrane reservoir formation | Regulation of plasma membrane invagination |
| ATG8 family (e.g., MAP1LC3B, GABARAP) | Regulation of vacuolar membrane invagination | Autophagy and vacuolar dynamics |
| Vacuolar membrane proteins | Physicochemical properties and invagination | Determinants of vacuolar invagination |
| Integrin-beta3 (ITGB3) | Podosome-mediated endocytosis | Plasma membrane invagination on RGD-membranes |
| Podosome components (e.g., actin regulators) | Adhesion and membrane invagination | Integrin endocytosis and matrix remodeling |
| Lysosomal membrane proteins | Membrane recycling | Lysosomal dynamics and recycling hypothesis |
| Zona glomerulosa markers | Rosette morphogenesis | Tissue-level membrane invagination |
| Appendicular invagination-related factors | Appendiceal biology | Clinical case observation |
| Caveolin-1 (CAV1) | Caveolae formation | Caveolar invagination and disease |
| Caveolin-2 (CAV2) | Caveolae formation | Caveolar invagination and disease |
| Cavin proteins | Caveolar stability | Caveolar invagination |
| EHD2 | Membrane remodeling | Caveolar dynamics |
| PACSIN2 | BAR domain protein | Membrane curvature in caveolae |
| Amphiphysin | BAR domain protein | Membrane invagination |
| Endophilin | BAR domain protein | Membrane invagination |
| SNX9 | BAR domain protein | Membrane invagination |
How Is membrane invagination Regulated?
Membrane invagination is regulated by a combination of protein-protein interactions, lipid composition, and mechanical forces [1, 4, 5]. BAR domain proteins and dynamins are key regulators that sense and generate membrane curvature [1, 4]. TMEM16F modulates lipid distribution to control membrane reservoir formation. Atg8 regulates vacuolar membrane invagination, likely through its conjugation to lipids and interaction with vacuolar proteins. The physicochemical properties of the membrane, including lipid packing and charge, also determine the efficiency of invagination. Additionally, cellular factors such as podosome components promote plasma membrane invagination and integrin endocytosis. These regulatory layers ensure that membrane invagination occurs at the right time and place.
membrane invagination and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| BIN1 | Caveolar invagination and myopathy | Knockout and point mutation in cell lines |
| DNM2 | Membrane reservoir defects and neuropathy | Knock-in of patient mutations |
| TMEM16F | Scott syndrome and membrane scrambling | Overexpression and knockout |
| ATG8 | Autophagy-related neurodegeneration | Knockout and tagged knock-in |
| ITGB3 | Cancer invasion and metastasis | Podosome formation assays |
Caveolar invagination and pathophysiological consequences
Defects in caveolar invagination, driven by BAR domain proteins, are associated with various pathophysiological conditions, including muscular dystrophies and cancer. Mutations in caveolar components can impair membrane shaping and lead to disease.
Lysosomal dysfunction and membrane recycling
Impaired lysosomal membrane invagination and recycling have been hypothesized to contribute to lysosomal storage disorders and neurodegenerative diseases. The lysosome relies on membrane invagination for proper recycling and function.
Cancer and cell adhesion
Podosome-mediated plasma membrane invagination and integrin-beta3 endocytosis are linked to cancer cell invasion and metastasis. Targeting these invagination processes may offer therapeutic opportunities.
Autophagy-related disorders
Atg8-mediated vacuolar membrane invagination is essential for autophagy; its dysregulation is implicated in neurodegenerative diseases and cancer. Understanding this process may reveal new therapeutic targets.
From membrane invagination-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X regulate membrane invagination? | CRISPR knockout cell lines [1, 2] |
| How do point mutations affect invagination? | CRISPR point mutation knock-in |
| Where does the protein localize during invagination? | Tagged knock-in with fluorescent reporter |
| Does overexpression drive invagination? | CRISPR overexpression models |
| What is the role of lipid composition? | CRISPR knockout of lipid-modifying enzymes |
| Can we screen for novel invagination regulators? | CRISPR library screening [1, 2] |
How to Study the membrane invagination Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell imaging | Dynamics of membrane invagination | Real-time visualization in cells |
| Electron microscopy | Ultrastructure of invaginations | High-resolution morphology |
| CRISPR knockout screens | Genes required for invagination | Functional genomics [1, 2] |
| Liposome assays | Protein-induced curvature | In vitro mechanism [1, 5] |
| Proteomics | Protein composition | Identification of invagination factors |
| Lipidomics | Lipid composition | Membrane property analysis |
| Fluorescence microscopy | Localization of tagged proteins | Knock-in reporter studies |
| Patch clamp | Membrane reservoir capacity | TMEM16F function |
Live-cell imaging and electron microscopy
Live-cell imaging with fluorescent membrane markers and electron microscopy are used to visualize membrane invagination dynamics at high resolution [1, 3]. These methods reveal the morphology and kinetics of invaginations.
CRISPR-based genetic screens
CRISPR knockout and activation screens can identify genes required for membrane invagination [1, 2]. Such screens have uncovered roles for BAR domain proteins and Atg8 in this process [1, 2].
Biochemical assays for membrane curvature
Liposome-based assays and membrane curvature sensors measure the ability of proteins to induce or sense invagination [1, 5]. These assays help dissect the physicochemical requirements for invagination.
Proteomics and lipidomics
Proteomic and lipidomic analyses identify protein and lipid changes during membrane invagination [4, 5]. They provide insights into the molecular composition of invaginated membranes.
How CRISPR Can Be Used to Study GO:0010324 membrane invagination
Knockout
CRISPR knockout of genes such as BIN1, DNM2, or ATG8 can abolish membrane invagination, revealing their essential roles [1, 2, 4]. Knockout cell lines are valuable for loss-of-function studies.
Point Mutation
CRISPR point mutation knock-in allows the introduction of disease-associated mutations to study their impact on membrane invagination. This approach is useful for modeling patient-specific defects.
Knock-in
Tagged knock-in of genes like ATG8 with fluorescent proteins enables real-time tracking of invagination dynamics. Knock-in models also facilitate biochemical isolation of invaginated membranes.
Overexpression
CRISPR-mediated overexpression of TMEM16F or dynamins can drive excessive membrane invagination and reservoir formation. Overexpression models help test sufficiency of candidate genes.
How EDITGENE Supports membrane invagination Research
Researchers studying membrane invagination-related genes often need to determine whether a candidate gene is causally involved in the process or merely correlated. EDITGENE provides a comprehensive suite of CRISPR services to enable such causal studies, from knockout to overexpression and library screening.
Contact EDITGENE today to design your custom CRISPR model for membrane invagination research.
Frequently Asked Questions About membrane invagination
What is membrane invagination (GO:0010324)?
Membrane invagination is the biological process defined as the infolding of a membrane, essential for endocytosis, autophagy, and organelle biogenesis [1, 2, 3].
What genes are involved in membrane invagination?
Key genes include BAR domain proteins, DNM1/2, TMEM16F, ATG8 family members, and ITGB3 [1, 2, 3, 4].
How is membrane invagination regulated?
It is regulated by curvature-sensing proteins, lipid composition, and mechanical forces, with BAR domain proteins and dynamins playing central roles [1, 4, 5].
What diseases are associated with defective membrane invagination?
Caveolar myopathies, lysosomal storage disorders, cancer, and autophagy-related neurodegeneration [1, 2, 3, 8].
What methods are used to study membrane invagination?
Live-cell imaging, electron microscopy, CRISPR screens, liposome assays, proteomics, and lipidomics [1, 3, 4, 5].
Can CRISPR be used to study membrane invagination?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to dissect gene function in membrane invagination [1, 2, 4].
What is the role of Atg8 in membrane invagination?
Atg8 regulates vacuolar membrane invagination, which is essential for autophagy.
How do BAR domain proteins contribute to membrane invagination?
BAR domain proteins sense and stabilize membrane curvature, facilitating caveolar invagination.
What is the role of TMEM16F in membrane invagination?
TMEM16F, together with dynamins, controls expansive plasma membrane reservoirs and invagination.
What is the connection between podosomes and membrane invagination?
Podosome formation promotes plasma membrane invagination and integrin-beta3 endocytosis.
Conclusion
Membrane invagination (GO:0010324) is a fundamental biological process that underlies diverse cellular functions, from endocytosis to autophagy and tissue morphogenesis [1, 2, 3, 6]. Its dysregulation is linked to a range of diseases, making it a critical area of research [1, 8]. Advances in CRISPR-based models and imaging technologies continue to unravel the molecular mechanisms of this process [1, 2, 4]. EDITGENE offers comprehensive services to support mechanistic and translational studies of membrane invagination.
References
- 1. Kessels MM et al.. 2020. The role of membrane-shaping BAR domain proteins in caveolar invagination: from mechanistic insights to pathophysiological consequences.. Biochem Soc Trans 48(1):137-146 PMID: 32104881
- 2. Ishii A et al.. 2019. Role of Atg8 in the regulation of vacuolar membrane invagination.. Sci Rep 9(1):14828 PMID: 31616012
- 3. Cao F et al.. 2020. Podosome formation promotes plasma membrane invagination and integrin-β3 endocytosis on a viscous RGD-membrane.. Commun Biol 3(1):117 PMID: 32170110
- 4. Deisl C et al.. 2021. TMEM16F and dynamins control expansive plasma membrane reservoirs.. Nat Commun 12(1):4990 PMID: 34404808
- 5. Kimura Y et al.. 2023. Physicochemical properties of the vacuolar membrane and cellular factors determine formation of vacuolar invaginations.. Sci Rep 13(1):16187 PMID: 37759072
- 6. Leng S et al.. 2021. Rosette morphology in zona glomerulosa formation and function.. Mol Cell Endocrinol 530:111287 PMID: 33891993
- 7. Arenal Vera JJ et al.. 1993. [Appendicular invagination].. Rev Esp Enferm Dig 84(2):116-8 PMID: 8398370
- 8. Dean RT. 1977. Lysosomes and membrane recycling. A hypothesis.. Biochem J 168(3):603-5 PMID: 606259
