GO:0045159 myosin II binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0045159 myosin II binding is a molecular function defined as binding to a class II myosin, the conventional double-headed myosin that includes muscle myosin.
• Myosin II binding proteins include supervillin, cripto, anillin, Rng2, and the myosin II heavy chain itself, which can bind F-actin and regulatory light chains.
• Myosin II binding is essential for cytokinesis, cell migration, and tissue regeneration, as shown by functional studies in Drosophila and mammalian cells.
• Structural studies reveal that myosin II binds F-actin in a double-headed manner, and strain affects head conformation, which is critical for force generation.
• Mutations in the actin-binding cleft of myosin II alter motor function, demonstrating the functional importance of these interfaces.
• CRISPR-based knockout, point mutation, knock-in, and overexpression models enable precise interrogation of myosin II binding proteins in health and disease.
Description
Myosin II binding (GO:0045159) is a molecular function that describes the selective interaction with class II myosins, which are the conventional double-headed myosins responsible for force generation in muscle and non-muscle cells. This binding event is fundamental to numerous cellular processes, including cytokinesis, cell migration, and tissue morphogenesis, because it positions and regulates myosin II motor activity. Researchers study myosin II binding to understand how accessory proteins control myosin II assembly, localization, and function in both normal physiology and disease. The QuickGO definition states that this function involves binding to any member of the class II myosins, a group that includes muscle myosin. Given its broad impact, myosin II binding is a focal point for investigations into cytoskeletal dynamics, cell division, and regeneration. This article synthesizes authoritative QuickGO data and verified PubMed literature to provide a research-grade overview of GO:0045159, covering its mechanism, key genes, disease relevance, and experimental approaches.
myosin II binding At A Glance
| GO ID | GO:0045159 |
|---|---|
| GO term | myosin II binding |
| Ontology | molecular_function |
| Synonym | none |
| Major function | Binding to class II myosins, including muscle myosin, to regulate contractile and motile processes |
| Definition source | QuickGO |
| Related processes | Cytokinesis, cell migration, tissue regeneration, muscle contraction |
| Example binding proteins | Supervillin, cripto, anillin, Rng2, myosin II heavy chain |
What Is GO:0045159?
GO:0045159 myosin II binding is defined by QuickGO as the binding to a class II myosin, any member of the class of conventional double-headed myosins that includes muscle myosin. In practice, this means a protein or domain physically interacts with myosin II, often through specific regions such as the actin-binding cleft or the tail domain, to modulate myosin II activity, stability, or localization. This function is distinct from binding to other myosin classes and is central to processes requiring contractile force.
Why Is myosin II binding Important in Cell Biology?
Myosin II binding is critically important because it governs the spatial and temporal control of myosin II, a motor protein that powers essential cellular events such as cytokinesis, cell migration, and tissue regeneration. Disruption of these interactions leads to defects in cell division and motility, which are hallmarks of developmental disorders and cancer progression. Understanding myosin II binding at the molecular level provides insights into how cells generate and transmit forces, and it offers potential targets for therapeutic intervention in diseases where myosin II function is dysregulated.
• Required for cytokinesis: supervillin binding to myosin II and synergism with anillin are essential for cell division.
• Regulates cell migration and invasion: anillin and Ect2 promote RhoA/myosin II-dependent confined migration.
• Involved in tissue regeneration: cripto binds myosin II and regulates stem cell function and regeneration.
• Affects muscle contraction: myosin II is the conventional muscle myosin, and its binding partners modulate contractility.
• Mutations in myosin II actin-binding cleft impair motor function, linking binding interfaces to physiological performance.
• Provides structural insights: double-headed binding of myosin II to F-actin reveals strain-dependent head conformations.
• Nonmuscle myosin II stability depends on light chain binding, which can be influenced by binding partners.
• Rng2 actin-binding domain sparsely bound on F-actin strongly inhibits actin movement on myosin II, showing regulatory complexity.
• Dysregulation of myosin II binding proteins is implicated in cancer cell invasion and metastasis.
• CRISPR models enable causal testing of myosin II binding genes in disease contexts.
Molecular Mechanism of myosin II binding
Recognition and Binding to Myosin II
In simple terms: Proteins that bind myosin II recognize specific regions on the myosin molecule and attach to them.
Myosin II binding proteins interact with class II myosins through defined structural elements. For example, supervillin contains F-actin and myosin II binding domains that mediate direct association with myosin II. Cripto was identified as a myosin II binding protein that regulates its function in stem cells and tissue regeneration. The binding specificity ensures that these proteins target conventional double-headed myosins, including muscle myosin, rather than other myosin classes.
Structural Basis of the Interaction
In simple terms: The shape and flexibility of myosin II and its binding partners determine how they fit together.
Structural studies have shown that myosin II binds F-actin with both heads, and strain affects the conformation of the head domains. The actin-binding cleft of myosin II is functionally critical; mutations in this cleft alter motor activity, highlighting the importance of precise interfacial contacts. Additionally, the actin-binding domain of Rng2, when sparsely bound on F-actin, strongly inhibits actin movement on myosin II, indicating that binding geometry can modulate motor output.
Regulation by Light Chains and Stability
In simple terms: Small subunits called light chains help keep myosin II stable and ready to bind partners.
Native nonmuscle myosin II stability and light chain binding are essential for its function in Drosophila melanogaster. The binding of regulatory light chains influences myosin II assembly and activity, which in turn affects interactions with myosin II binding proteins. This regulation ensures that myosin II binding occurs in the appropriate cellular context.
Functional Consequences in Cytokinesis and Migration
In simple terms: When proteins bind myosin II, they help cells divide and move.
Supervillin binding to myosin II, together with anillin, is required for cytokinesis. Anillin and Ect2 promote RhoA/myosin II-dependent confined migration and invasion, demonstrating that myosin II binding proteins are integral to cell motility. These functional outcomes underscore the physiological importance of GO:0045159 in cell division and migration.
Key Genes Involved in GO:0045159 myosin II binding
The following genes and proteins are experimentally validated to participate in myosin II binding (GO:0045159) or to regulate myosin II function through direct interactions.
| Gene | Major Role | Research Relevance |
|---|---|---|
| MYH9 | Non-muscle myosin II heavy chain; binds F-actin and light chains | Mutations cause platelet disorders; model for cytokinesis and migration |
| MYH10 | Non-muscle myosin II heavy chain isoform | Studied in cell motility and adhesion |
| MYH11 | Smooth muscle myosin II heavy chain | Vascular smooth muscle contraction; knockout models |
| MYL6 | Myosin light chain 6; stabilizes myosin II | Light chain binding affects stability |
| MYL9 | Regulatory light chain; controls myosin II activity | Phosphorylation regulates contraction |
| SVIL | Supervillin; binds F-actin and myosin II | Required for cytokinesis; synergizes with anillin |
| ANLN | Anillin; binds myosin II and actin | Essential for cytokinesis and migration |
| ECT2 | RhoA guanine nucleotide exchange factor; promotes myosin II activation | Invasion and confined migration |
| RHOA | Small GTPase; activates myosin II via ROCK | Regulates contractility and migration |
| CRIPTO | Cripto; binds myosin II and regulates stem cell function | Tissue regeneration and stem cell biology |
| RNG2 | Fission yeast IQGAP; actin-binding domain inhibits myosin II motility | Model for actomyosin regulation |
| ACTB | Beta-actin; forms F-actin tracks for myosin II | Cytoskeletal dynamics |
| ACTG1 | Gamma-actin; component of actin filaments | Cell motility and structure |
| TPM1 | Tropomyosin; regulates actin-myosin interaction | Muscle and non-muscle contractility |
| CALD1 | Caldesmon; binds actin and myosin II | Smooth muscle contraction |
| MYH7 | Cardiac muscle myosin heavy chain | Cardiomyopathy models |
| MYH2 | Fast skeletal muscle myosin heavy chain | Muscle physiology |
| MYH3 | Embryonic skeletal muscle myosin heavy chain | Development and disease |
How Is myosin II binding Regulated?
Myosin II binding is regulated at multiple levels. Light chain phosphorylation controls myosin II assembly and activity, which in turn modulates binding to partners such as supervillin and anillin. RhoA signaling through Ect2 promotes RhoA/myosin II-dependent confined migration, linking upstream GTPase activity to myosin II binding functions. Additionally, the stability of nonmuscle myosin II depends on proper light chain binding, and disruption of this regulation affects interactions with binding proteins. Structural strain on myosin II heads during F-actin binding also influences head conformation, providing a mechanical layer of regulation.
myosin II binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| ANLN | Cancer invasion and metastasis | Knockout in cancer cell lines; invasion assays |
| SVIL | Cytokinesis failure and genomic instability | Knockout in HeLa or U2OS cells; live imaging |
| CRIPTO | Regenerative defects and stem cell dysfunction | Knockout in embryonic stem cells; regeneration models |
| MYH9 | Platelet disorders and hearing loss | Point mutation knock-in in mice |
| MYH7 | Cardiomyopathy | Knock-in of patient mutations in iPSC-derived cardiomyocytes |
Myosin II binding in cancer invasion and metastasis
Anillin and Ect2 promote RhoA/myosin II-dependent confined migration and invasion, processes that are critical for cancer metastasis. Supervillin binding to myosin II is required for cytokinesis, and its dysregulation could contribute to genomic instability in cancer. These findings suggest that myosin II binding proteins are potential therapeutic targets in oncology.
Myosin II binding in tissue regeneration and stem cells
Cripto was identified as a myosin II binding protein that regulates cripto function in stem cells and tissue regeneration. This interaction is important for regenerative medicine and understanding stem cell behavior.
Myosin II binding in muscle and cytoskeletal disorders
Mutations in the actin-binding cleft of myosin II affect motor function, which can lead to muscle weakness and cytoskeletal defects. Nonmuscle myosin II stability and light chain binding are essential, and defects may contribute to diseases such as platelet disorders.
From myosin II binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of supervillin impair cytokinesis? | SVIL knockout cell line (e.g., HeLa) with live-cell imaging |
| Does a point mutation in myosin II actin-binding cleft alter motor function? | CRISPR point mutation knock-in in MYH9 or MYH10 |
| Does cripto-myosin II binding regulate stem cell regeneration? | CRIPTO knockout or tagged knock-in in stem cells |
| Does anillin promote confined migration? | ANLN knockout in cancer cells; 3D migration assays |
| Does overexpression of Rng2 actin-binding domain inhibit myosin II motility? | Overexpression in fission yeast or mammalian cells |
| Does light chain binding affect myosin II stability? | MYL6 or MYL9 knockout in Drosophila or mammalian cells |
How to Study the myosin II binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell fluorescence microscopy | Localization and dynamics of myosin II and binding partners | Cytokinesis and migration studies |
| In vitro actin motility assay | Speed and direction of actin movement on myosin II | Motor function and regulation |
| Cryo-electron microscopy | High-resolution structure of myosin II-actin complexes | Structural basis of binding and strain effects |
| Co-immunoprecipitation / mass spectrometry | Protein-protein interactions | Identification of novel myosin II binding proteins |
| FRET biosensors | Conformational changes and binding dynamics in live cells | Real-time regulation of myosin II binding |
| CRISPR knockout screening | Phenotypic effects of losing candidate genes | Cytokinesis and migration pathways |
| Phospho-proteomics | Light chain phosphorylation status | Regulation of myosin II activity |
| 3D invasion assays | Cell migration through confined environments | Cancer invasion and metastasis |
Live-cell imaging of myosin II dynamics
Fluorescently tagged myosin II and binding proteins can be visualized in live cells to track localization and dynamics during cytokinesis and migration. This method reveals real-time interactions and is often combined with knockout or knock-in models.
In vitro actin motility assays
Reconstituted actin-myosin motility assays measure the movement of actin filaments on myosin II coated surfaces, and can be used to test the effect of binding proteins such as Rng2 or mutant myosin II. These assays provide quantitative data on motor function.
Structural biology and cryo-electron microscopy
Cryo-EM and X-ray crystallography reveal the structural basis of myosin II binding to F-actin and the effect of strain on head conformation. These techniques are essential for understanding the molecular details of GO:0045159.
Proteomics and co-immunoprecipitation
Co-immunoprecipitation coupled with mass spectrometry identifies novel myosin II binding proteins and maps interaction networks. This approach can be applied to cells with CRISPR-engineered tags for endogenous proteins.
How CRISPR Can Be Used to Study GO:0045159 myosin II binding
Knockout
CRISPR knockout of genes encoding myosin II binding proteins, such as SVIL or ANLN, can reveal their essential roles in cytokinesis and migration. Knockout cell lines are valuable for phenotypic screens and live-cell imaging.
Point Mutation
Introducing point mutations in the actin-binding cleft of myosin II (e.g., MYH9) using CRISPR base editing or homology-directed repair allows functional characterization of specific residues. Such models help dissect the contribution of individual binding interfaces.
Knock-in
Knock-in of fluorescent or affinity tags into endogenous myosin II or its binding partners enables real-time tracking and proteomic analysis under native regulation. Tagged knock-in models are ideal for studying dynamic interactions.
Overexpression
Overexpression of myosin II binding domains, such as the Rng2 actin-binding domain, can act as a dominant-negative inhibitor of myosin II motility. This approach is useful for probing the consequences of excess binding.
How EDITGENE Supports myosin II binding Research
Researchers studying myosin II binding-related genes often need to determine whether a candidate gene is causally involved in cytokinesis, migration, or regeneration. EDITGENE provides a comprehensive suite of CRISPR services to generate precisely engineered cell models, enabling rigorous functional validation of GO:0045159 components.
Contact EDITGENE today to design your custom CRISPR model for myosin II binding research.
Frequently Asked Questions About myosin II binding
What is GO:0045159 myosin II binding?
GO:0045159 is a molecular function term defined as binding to a class II myosin, any member of the conventional double-headed myosins that includes muscle myosin.
What genes are involved in myosin II binding?
Key genes include MYH9, MYH10, SVIL, ANLN, ECT2, RHOA, CRIPTO, and RNG2, among others.
How does myosin II binding affect cytokinesis?
Supervillin binding to myosin II and its synergism with anillin are required for cytokinesis, as shown by knockout studies.
What diseases are associated with myosin II binding?
Dysregulation of myosin II binding proteins is linked to cancer invasion, metastasis, and tissue regeneration defects.
What methods are used to study myosin II binding?
Common methods include live-cell imaging, in vitro actin motility assays, cryo-EM, co-immunoprecipitation, and CRISPR screens.
Can CRISPR be used to study myosin II binding?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models enable precise functional studies of myosin II binding genes.
What is the role of anillin in myosin II binding?
Anillin binds myosin II and is essential for cytokinesis and confined cell migration, often in synergy with supervillin.
How does cripto interact with myosin II?
Cripto was identified as a myosin II binding protein that regulates cripto function in stem cells and tissue regeneration.
What structural features define myosin II binding?
The actin-binding cleft and double-headed binding to F-actin are critical, and strain affects head conformation.
What model systems are used for myosin II binding research?
Model systems include Drosophila melanogaster, fission yeast, mammalian cell lines, and CRISPR-engineered cells.
Conclusion
GO:0045159 myosin II binding is a fundamental molecular function that underpins cytokinesis, cell migration, and tissue regeneration through interactions with class II myosins. The integration of structural, biochemical, and CRISPR-based approaches has illuminated the key proteins and mechanisms involved, from supervillin and anillin to cripto and Rng2. Continued research using precise genome editing will further clarify how these interactions contribute to health and disease, offering new avenues for therapeutic intervention.
References
- 1. Hojjatian A et al.. 2023. Double-headed binding of myosin II to F-actin shows the effect of strain on head structure.. J Struct Biol 215(3):107995 PMID: 37414375
- 2. Hayakawa Y et al.. 2023. Actin-binding domain of Rng2 sparsely bound on F-actin strongly inhibits actin movement on myosin II.. Life Sci Alliance 6(1) PMID: 36288901
- 3. Fujita-Becker S et al.. 2006. The actin-binding cleft: functional characterisation of myosin II with a strut mutation.. J Muscle Res Cell Motil 27(2):115-23 PMID: 16450056
- 4. Chen Y et al.. 2003. F-actin and myosin II binding domains in supervillin.. J Biol Chem 278(46):46094-106 PMID: 12917436
- 5. Hoover M et al.. 2019. Identification of myosin II as a cripto binding protein and regulator of cripto function in stem cells and tissue regeneration.. Biochem Biophys Res Commun 509(1):69-75 PMID: 30579599
- 6. Franke JD et al.. 2006. Native nonmuscle myosin II stability and light chain binding in Drosophila melanogaster.. Cell Motil Cytoskeleton 63(10):604-22 PMID: 16917818
- 7. Smith TC et al.. 2013. Supervillin binding to myosin II and synergism with anillin are required for cytokinesis.. Mol Biol Cell 24(23):3603-19 PMID: 24088567
- 8. Tran AT et al.. 2025. Cytoplasmic anillin and Ect2 promote RhoA/myosin II-dependent confined migration and invasion.. Nat Mater 24(9):1476-1488 PMID: 40571734
