GO:0060327 cytoplasmic actin-based contraction involved in cell motility: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0060327 describes the actin filament-based movement in which cytoplasmic actin filaments slide past one another to produce a contraction that propels a cell from one place to another.
• This process is distinct from muscle contraction and is driven by non-muscle myosin II motors that generate force on dynamic actin networks.
• Cytoplasmic actin-based contraction underlies diverse motile behaviors including blebbing, cortical oscillations, and embryonic morphogenesis.
• Regulation depends on myosin light chain phosphorylation and dephosphorylation cycles that control myosin II assembly and contractile activity.
• The biophysical output of this process can be reconstituted in vitro using purified actin, myosin, and accessory proteins, enabling quantitative analysis.
• Dysregulation of cytoplasmic actin-based contraction is implicated in cancer cell invasion, immune cell migration, and developmental defects.
Description
Cytoplasmic actin-based contraction involved in cell motility (GO:0060327) is a biological process defined as the actin filament-based movement by which cytoplasmic actin filaments slide past one another, resulting in a contraction that propels the cell from one place to another. This term captures a fundamental motile mechanism that operates in non-muscle cells, distinct from sarcomeric muscle contraction, and is essential for processes ranging from embryonic morphogenesis to immune surveillance. The contraction is powered by the interaction between actin filaments and non-muscle myosin II motors, which convert chemical energy into mechanical force. Researchers study this process to understand how cells generate the forces required for migration, shape change, and tissue remodeling. The importance of GO:0060327 extends to human health, as defects in actin-based contractility contribute to cancer metastasis, immune disorders, and developmental abnormalities. This article synthesizes authoritative QuickGO annotation data and verified PubMed literature to provide a research-grade overview of the mechanism, key genes, regulatory control, disease relevance, and experimental methods for studying cytoplasmic actin-based contraction involved in cell motility.
cytoplasmic actin-based contraction involved in cell motility At A Glance
| GO ID | GO:0060327 |
|---|---|
| GO term | cytoplasmic actin-based contraction involved in cell motility |
| Ontology | biological_process |
| Synonym | None listed in QuickGO |
| Definition | The actin filament-based movement by which cytoplasmic actin filaments slide past one another resulting in a contraction that propels the cell from one place to another. |
| Major function | Generation of contractile forces for cell motility and shape change |
| Cellular context | Cytoplasm, actin cytoskeleton, non-muscle cells |
| Key molecular players | Actin filaments, non-muscle myosin II, myosin light chain kinase, Rho GTPases |
| Related processes | Cell migration, blebbing, cortical oscillations, cytokinesis |
What Is GO:0060327?
GO:0060327 is defined by QuickGO as the actin filament-based movement by which cytoplasmic actin filaments slide past one another resulting in a contraction that propels the cell from one place to another. In simpler terms, it is the process by which a cell uses its internal actin cytoskeleton, together with motor proteins such as myosin, to squeeze itself and move forward. Unlike muscle contraction, which occurs in specialized sarcomeric structures, this process takes place in the cytoplasm of non-muscle cells and is often transient and highly dynamic. The contraction is driven by the relative sliding of actin filaments, a mechanism that has been reconstituted in vitro and studied in systems such as nematode sperm and epithelial cells.
Why Is cytoplasmic actin-based contraction involved in cell motility Important in Cell Biology?
Cytoplasmic actin-based contraction involved in cell motility is a central mechanism by which cells generate the mechanical forces needed to move, change shape, and remodel tissues. It is essential for embryonic development, where coordinated contractions drive morphogenetic movements, and for immune cell function, where actin-based forces enable leukocyte migration and extravasation. The process also contributes to pathological conditions such as cancer invasion and metastasis, where tumor cells hijack contractile machinery to disseminate. Understanding GO:0060327 at the molecular level provides insights into fundamental cell biology and offers potential targets for therapeutic intervention in diseases characterized by aberrant cell motility.
• Drives embryonic morphogenesis and tissue remodeling during development.
• Enables immune cell migration and surveillance by generating contractile forces.
• Underlies blebbing motility, a mode of cell movement used in confined environments.
• Contributes to cortical oscillations that establish cell polarity.
• Is hijacked in cancer metastasis to promote invasion and dissemination.
• Provides a model system for studying force generation by actin-myosin networks.
• Regulated by phosphorylation of myosin light chain, linking signaling to mechanics.
• Can be reconstituted in vitro, enabling quantitative biophysical analysis.
• Relevant to developmental defects when contractility is impaired.
• Potential target for therapies aimed at modulating cell motility in disease.
What Happens During cytoplasmic actin-based contraction involved in cell motility?
Initiation by signaling and actin polymerization
In simple terms: The cell receives a signal that tells it to start moving, and it begins to build actin filaments.
Cytoplasmic actin-based contraction is initiated by signaling pathways that activate Rho GTPases and their downstream effectors, leading to actin polymerization and myosin II activation. The assembly of actin filaments provides the tracks along which myosin motors can slide, and the initial polymerization is often nucleated by formins or the Arp2/3 complex. In epithelial cells, this initiation is tightly coupled to phosphorylation of the myosin II light chain, which triggers myosin assembly and contractile activity.
Myosin II activation and force generation
In simple terms: Molecular motors called myosin II grab the actin filaments and pull them, creating force.
Non-muscle myosin II is the primary motor that generates contractile force during cytoplasmic actin-based contraction. Activation of myosin II requires phosphorylation of its regulatory light chain by myosin light chain kinase (MLCK) or Rho-associated kinase (ROCK), which promotes myosin filament assembly and ATPase activity. The sliding of actin filaments past one another, driven by myosin II, produces the contraction that propels the cell. This mechanism has been studied in reconstituted systems, where actin and myosin together generate contractile forces.
Actin filament sliding and network contraction
In simple terms: The actin filaments slide over each other, making the network shrink and pull the cell forward.
The core of GO:0060327 is the sliding of cytoplasmic actin filaments past one another, which results in a contraction. This sliding is mediated by myosin II motors that walk along actin filaments, pulling them in opposite directions and causing the network to contract. In motile cells, this contraction is often asymmetric, generating forces that push or pull the cell body forward. Studies in Caenorhabditis elegans sperm and other systems have revealed that the dynamics of actin and myosin interactions are finely tuned to produce directed movement.
Coupling to cell motility and shape change
In simple terms: The contraction is linked to the cell's movement, helping it crawl or change shape.
The contractile forces generated by cytoplasmic actin-based contraction are coupled to cell motility through adhesion complexes and the cytoskeleton. In blebbing motility, for example, contraction of the actin cortex drives the formation of membrane blebs that propel the cell forward. In embryonic morphogenesis, coordinated contractions in groups of cells drive tissue movements. The process is also linked to cortical oscillations that establish cell polarity, as observed in lymphoblasts.
Termination and recycling
In simple terms: The contraction stops and the cell recycles the components for another round of movement.
Termination of cytoplasmic actin-based contraction involves dephosphorylation of myosin light chain by myosin phosphatases, leading to myosin disassembly and relaxation. Actin filaments are depolymerized or reorganized by actin-binding proteins such as cofilin and profilin, allowing the cell to reset its cytoskeleton for subsequent motile events. This dynamic cycling is essential for sustained cell motility and for adapting to changing environmental cues.
Key Genes Involved in GO:0060327 cytoplasmic actin-based contraction involved in cell motility
The following genes and proteins are central to cytoplasmic actin-based contraction involved in cell motility, based on their established roles in actin dynamics, myosin motor activity, and regulatory signaling.
| Gene | Major Role | Research Relevance |
|---|---|---|
| ACTB | Beta-actin, major component of actin filaments | Core structural element for contraction; knockout lethal in many organisms |
| ACTG1 | Gamma-actin, cytoplasmic actin isoform | Contributes to actin network in non-muscle cells |
| MYH9 | Non-muscle myosin II heavy chain | Primary motor for contractile force; mutations cause platelet disorders |
| MYH10 | Non-muscle myosin IIB heavy chain | Involved in neuronal migration and cytokinesis |
| MYL9 | Myosin regulatory light chain | Phosphorylation controls myosin II activation |
| MYLK | Myosin light chain kinase | Phosphorylates myosin light chain to initiate contraction |
| ROCK1 | Rho-associated kinase 1 | Regulates myosin light chain phosphorylation and actin dynamics |
| ROCK2 | Rho-associated kinase 2 | Inhibits myosin phosphatase, promoting contractility |
| RHOA | Rho GTPase | Master regulator of actin-myosin contractility |
| CDC42 | Rho GTPase | Controls actin polymerization and filopodia formation |
| RAC1 | Rho GTPase | Regulates lamellipodia and actin reorganization |
| PFN1 | Profilin-1 | Promotes actin polymerization; mutations linked to ALS |
| CFL1 | Cofilin-1 | Depolymerizes actin filaments, enabling turnover |
| ARP2/3 complex | Actin nucleator | Generates branched actin networks for force production |
| FMNL2 | Formin-like 2 | Nucleates linear actin filaments for contractility |
| TAGLN | Transgelin | Actin-binding protein that stabilizes actin filaments |
| VCL | Vinculin | Links actin cytoskeleton to focal adhesions during motility |
How Is cytoplasmic actin-based contraction involved in cell motility Regulated?
Cytoplasmic actin-based contraction involved in cell motility is regulated primarily through reversible phosphorylation of the myosin II regulatory light chain. Myosin light chain kinase (MLCK) phosphorylates the light chain to activate myosin II, while myosin light chain phosphatase dephosphorylates it to promote relaxation. Rho-associated kinases (ROCK1 and ROCK2) modulate this balance by inhibiting myosin phosphatase and directly phosphorylating the light chain, thereby enhancing contractility. Upstream, Rho GTPases such as RHOA act as molecular switches that integrate extracellular signals to control actin polymerization and myosin activation. Additionally, actin-binding proteins like cofilin and profilin regulate filament turnover, ensuring that contraction is dynamic and reversible. This multilayered regulation allows cells to rapidly adjust contractile force in response to mechanical and chemical cues.
cytoplasmic actin-based contraction involved in cell motility and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| MYH9 | MYH9-related disorders (platelet defects, hearing loss) | Knock-in mouse models with patient mutations |
| RHOA | Cancer metastasis, cell migration | Knockout and overexpression in cancer cell lines |
| ROCK1 | Cancer invasion, fibrosis | Point mutation to inhibit kinase activity |
| PFN1 | Amyotrophic lateral sclerosis (ALS) | Knock-in of ALS-associated mutations in neurons |
| ACTB | Baraitser-Winter syndrome | Knock-in of patient mutations in iPSCs |
Cancer invasion and metastasis
Cytoplasmic actin-based contraction is exploited by cancer cells to invade surrounding tissues and metastasize. Upregulation of non-muscle myosin II and Rho GTPase signaling enhances contractility, enabling tumor cells to squeeze through confined spaces and migrate. Targeting components of this pathway, such as ROCK or myosin II, has been explored as a strategy to inhibit metastasis in preclinical models.
Immune cell migration and inflammation
Immune cells rely on actin-based contraction for migration to sites of infection and inflammation. Defects in myosin II or its regulators impair leukocyte motility and can lead to immune deficiencies. Understanding how GO:0060327 is controlled in immune cells may inform therapies for inflammatory diseases.
Developmental disorders
Proper regulation of cytoplasmic actin-based contraction is essential for embryonic morphogenesis. Disruption of contractile machinery in model organisms such as Caenorhabditis elegans leads to defects in cell migration and tissue formation. In humans, mutations in actin or myosin genes can cause developmental abnormalities, though direct links to GO:0060327 require further study.
From cytoplasmic actin-based contraction involved in cell motility-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of MYH9 impair cell motility? | MYH9 knockout cell line (e.g., HeLa or MEFs) |
| How does a specific ROCK1 mutation affect contractility? | Point-mutation knock-in of kinase-dead ROCK1 |
| Can tagged myosin II be used to track contraction dynamics? | Knock-in of fluorescent protein tag at MYH9 locus |
| Does overexpression of RHOA increase metastatic potential? | Overexpression of constitutively active RHOA in cancer cells |
| What is the role of PFN1 in actin-based motility? | PFN1 knockout and rescue with wild-type or mutant |
| How does ACTB mutation affect actin network contraction? | Knock-in of ACTB mutations in iPSC-derived cells |
How to Study the cytoplasmic actin-based contraction involved in cell motility Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell fluorescence microscopy | Actin and myosin dynamics | Visualizing contraction in migrating cells |
| Traction force microscopy | Cellular traction forces | Quantifying contractile force generation |
| In vitro reconstitution | Minimal components for contraction | Biophysical analysis of actin-myosin sliding |
| Phospho-Western blot | Myosin light chain phosphorylation | Assessing myosin II activation state |
| FRAP (fluorescence recovery after photobleaching) | Actin turnover rates | Measuring actin dynamics in contractile networks |
| Optogenetics | Spatiotemporal control of contractility | Inducing localized contractions with light |
| Atomic force microscopy | Cell stiffness and cortical tension | Relating contractility to mechanical properties |
Live-cell imaging of actin and myosin dynamics
Fluorescence microscopy of cells expressing GFP-tagged actin or myosin II allows real-time visualization of contractile events. This method reveals the spatiotemporal dynamics of actin filament sliding and network contraction during cell motility.
Traction force microscopy
Traction force microscopy measures the mechanical forces exerted by cells on their substrate, providing quantitative data on contractile output. This technique has been used to study actin-based forces in migrating cells.
In vitro reconstitution assays
Purified actin, myosin, and accessory proteins can be combined in vitro to reconstitute contraction. Such assays have been instrumental in dissecting the minimal components required for actin-based contraction and in testing the effects of regulatory proteins.
Phosphorylation analysis
Western blotting with phospho-specific antibodies against myosin light chain is used to monitor the activation state of myosin II. This method links signaling events to contractile activity and is widely used in studies of GO:0060327 regulation.
How CRISPR Can Be Used to Study GO:0060327 cytoplasmic actin-based contraction involved in cell motility
Knockout
CRISPR knockout of genes such as MYH9, RHOA, or ROCK1 can abolish or reduce cytoplasmic actin-based contraction, allowing researchers to test their requirement for cell motility. Knockout cell lines are valuable for loss-of-function studies and for identifying compensatory mechanisms.
Point Mutation
Point mutations can be introduced to mimic disease-associated variants or to abrogate specific phosphorylation sites. For example, mutating the myosin light chain phosphorylation site can prevent myosin II activation, providing insights into the role of phosphorylation in contraction.
Knock-in
Knock-in of fluorescent tags (e.g., GFP) at endogenous loci enables real-time tracking of proteins like myosin II or actin without overexpression artifacts. This approach is ideal for studying the dynamics of contractile machinery in live cells.
Overexpression
Overexpression of constitutively active RHOA or myosin II mutants can enhance contractility and promote motile phenotypes. This strategy is used to investigate gain-of-function effects and to model diseases characterized by excessive contractility, such as cancer metastasis.
How EDITGENE Supports cytoplasmic actin-based contraction involved in cell motility Research
Researchers studying cytoplasmic actin-based contraction involved in cell motility-related genes often need to determine whether a candidate gene is causally involved in the process or merely correlated with it. EDITGENE provides a comprehensive suite of CRISPR-based services to enable precise genetic manipulation and functional interrogation of these genes in relevant cell models.
Contact EDITGENE today to design your custom CRISPR model for cytoplasmic actin-based contraction involved in cell motility research.
Frequently Asked Questions About cytoplasmic actin-based contraction involved in cell motility
What is GO:0060327?
GO:0060327 is the Gene Ontology term for cytoplasmic actin-based contraction involved in cell motility, defined as the actin filament-based movement by which cytoplasmic actin filaments slide past one another resulting in a contraction that propels the cell from one place to another.
What genes are involved in cytoplasmic actin-based contraction involved in cell motility?
Key genes include ACTB, MYH9, MYL9, MYLK, RHOA, ROCK1, and PFN1, among others, which encode actin, myosin, and regulatory proteins.
How is cytoplasmic actin-based contraction regulated?
It is primarily regulated by phosphorylation of the myosin II regulatory light chain by MLCK and ROCK, and dephosphorylation by myosin phosphatases.
What diseases are associated with defects in actin-based contraction?
Defects are linked to cancer metastasis, immune disorders, and developmental abnormalities.
What methods are used to study GO:0060327?
Common methods include live-cell imaging, traction force microscopy, in vitro reconstitution, and phosphorylation analysis.
Can CRISPR be used to study cytoplasmic actin-based contraction?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to dissect gene function in this process.
What is the difference between muscle contraction and cytoplasmic actin-based contraction?
Muscle contraction occurs in sarcomeres of muscle cells, while cytoplasmic actin-based contraction occurs in non-muscle cells and is not organized into sarcomeres.
Which proteins generate force in cytoplasmic actin-based contraction?
Non-muscle myosin II motors generate force by sliding actin filaments past one another.
How does blebbing relate to GO:0060327?
Blebbing is a mode of cell motility driven by actin-based contraction of the cortex, which propels the cell forward.
What model organisms are used to study actin-based contraction?
Caenorhabditis elegans and mammalian cell lines are commonly used to study actin-based forces in morphogenesis and motility.
Conclusion
Cytoplasmic actin-based contraction involved in cell motility (GO:0060327) is a fundamental biological process that powers non-muscle cell movement through the sliding of actin filaments driven by myosin II motors. Its regulation by phosphorylation and Rho GTPase signaling ensures dynamic control, and its dysregulation contributes to cancer, immune disorders, and developmental defects. Researchers can leverage CRISPR-based models and advanced imaging techniques to dissect the molecular players and pathways involved. EDITGENE offers comprehensive services to support these investigations, from knockout and knock-in cell lines to library screening and bioinformatics.
References
- 1. Charras GT. 2008. A short history of blebbing.. J Microsc 231(3):466-78 PMID: 18755002
- 2. Marston DJ et al.. 2006. Actin-based forces driving embryonic morphogenesis in Caenorhabditis elegans.. Curr Opin Genet Dev 16(4):392-8 PMID: 16782324
- 3. Bottino D et al.. 2002. How nematode sperm crawl.. J Cell Sci 115(Pt 2):367-84 PMID: 11839788
- 5. Maravillas-Montero JL et al.. 2012. The myosin family: unconventional roles of actin-dependent molecular motors in immune cells.. J Leukoc Biol 91(1):35-46 PMID: 21965174
- 6. Janson LW et al.. 1991. Modulation of contraction by gelation/solation in a reconstituted motile model.. J Cell Biol 114(5):1005-15 PMID: 1651941
- 7. Watanabe T et al.. 2007. Regulation of myosin II dynamics by phosphorylation and dephosphorylation of its light chain in epithelial cells.. Mol Biol Cell 18(2):605-16 PMID: 17151359
- 8. Bornens M et al.. 1989. The cortical microfilament system of lymphoblasts displays a periodic oscillatory activity in the absence of microtubules: implications for cell polarity.. J Cell Biol 109(3):1071-83 PMID: 2570076
