Cytoskeleton in Cell Structure Maintenance, Migration, and Disease Mechanisms

The cytoskeleton is a dynamic fibrous network composed of microfilaments, microtubules, and intermediate filaments, mainly consisting of actin, tubulin, and different types of intermediate filament proteins. The cytoskeleton not only maintains cell morphology, cell polarity, and intracellular spatial organization, but also participates in cell migration, cell division, intracellular transport, mechanosensing, and signal transduction. It is a core system that connects structural changes in cells with functional responses.

Keywords: cytoskeleton; actin; microtubule; intermediate filament; cell migration; FAK; Paxillin; Rho GTPase; mechanotransduction

1 Basic Components of the Cytoskeleton

1.1 Microfilaments

Microfilaments are mainly formed by actin polymerization and often participate in the formation of the cell cortex, stress fibers, lamellipodia, filopodia, contractile rings, and adhesion structures in the form of F-actin. Microfilaments are highly dynamic and can rapidly polymerize and depolymerize, making them key structures for cell shape changes, migration, cytokinesis, and mechanical force transmission.

(1) Structural characteristics

G-actin can polymerize to form F-actin. F-actin is polarized, and its plus end and minus end have different polymerization dynamics. Cells regulate F-actin network morphology and contractile force through molecules such as the Arp2/3 complex, formins, cofilin, profilin, and myosin.

(2) Functional positioning

Microfilaments mainly participate in cell edge extension, focal adhesion linkage, cell contraction, membrane protrusion formation, and cytokinesis. Lamellipodia and filopodia at the leading edge of migrating cells depend on F-actin remodeling, while rear retraction depends on myosin-mediated actin contraction.

1.2 Microtubules

Microtubules are formed by polymerization of α/β-tubulin heterodimers and exhibit clear polarity and dynamic instability. Microtubules extend from the centrosome or microtubule-organizing center toward the cell periphery and participate in intracellular transport, cell polarity establishment, spindle formation, chromosome segregation, and organelle positioning.

(1) Structural characteristics

Microtubules are composed of protofilaments formed by α-tubulin and β-tubulin. Their plus ends usually show higher dynamics, while minus ends are mostly anchored at the microtubule-organizing center. Microtubule polymerization, catastrophe, and rescue are regulated by GTP hydrolysis, microtubule-associated proteins, and microtubule stability regulators.

(2) Functional positioning

Microtubules provide tracks for intracellular transport. Kinesin and dynein transport vesicles, mitochondria, protein complexes, and RNA granules along microtubules. During cell division, microtubules form the mitotic spindle to ensure correct chromosome alignment and segregation.

1.3 Intermediate Filaments

Intermediate filaments (IFs) are cytoskeletal components with strong mechanical support capacity and have a diameter between that of microfilaments and microtubules. Different cell types express different intermediate filament proteins, so intermediate filaments are often used to determine tissue origin and cell differentiation status.

(1) Structural characteristics

Intermediate filaments do not have clear polarity like microfilaments and microtubules. They mainly provide tensile resistance and structural stability. Their assembly state is regulated by phosphorylation, glycosylation, proteolysis, and other modifications.

(2) Representative proteins

Keratin is commonly found in epithelial cells, vimentin in mesenchymal cells, desmin in muscle cells, GFAP in astrocytes, neurofilament proteins in neurons, and lamins in the nuclear skeleton.

Table 1 Comparison of the Three Major Cytoskeletal Components

Component	Main Structural Proteins	Typical Structures	Main Functions	Common Research Indicators
Microfilaments	Actin	F-actin, stress fibers, pseudopodia, contractile ring	Cell morphology, migration, contraction, cytokinesis	F-actin, Phalloidin staining, Cofilin, Myosin II
Microtubules	α/β-Tubulin	Microtubule network, spindle, axonal microtubules	Intracellular transport, cell polarity, chromosome segregation	α-tubulin, β-tubulin, Acetylated tubulin, EB1
Intermediate filaments	Keratin, Vimentin, Desmin, GFAP, Neurofilament, Lamin	Cytoplasmic intermediate filament network, nuclear lamina	Mechanical support, tissue specificity, cell differentiation status	Vimentin, Keratin, Desmin, GFAP, Lamin

2 Dynamic Regulation of the Cytoskeleton

2.1 Polymerization and Depolymerization

The cytoskeleton is not a fixed scaffold, but a dynamic system that continuously undergoes assembly, disassembly, and remodeling. Cells rapidly respond to external stimuli and internal state changes by regulating microfilament polymerization, microtubule dynamic instability, and intermediate filament reorganization.

(1) Microfilament dynamics

Actin polymerization drives extension of the cell leading edge. Cofilin-mediated severing promotes renewal of existing F-actin. The Arp2/3 complex promotes formation of branched actin networks, while formins promote elongation of linear actin bundles.

(2) Microtubule dynamics

The plus ends of microtubules continuously undergo growth, catastrophe, and rescue. Microtubule plus-end binding proteins such as EB1 can mark dynamic microtubule ends, while acetylated tubulin is commonly used to observe more stable microtubule structures.

(3) Intermediate filament reorganization

Intermediate filaments are relatively less dynamic, but they can still undergo reorganization during cell migration, division, stress, and epithelial-mesenchymal transition. Vimentin reorganization is often associated with a mesenchymal phenotype, migratory capacity, and changes in cellular mechanics.

2.2 Post-Translational Modifications

Cytoskeletal proteins can undergo phosphorylation, acetylation, detyrosination, ubiquitination, SUMOylation, O-GlcNAcylation, and other modifications. These modifications affect cytoskeletal assembly, stability, protein interactions, and cellular function.

Table 2 Common Regulatory Modes of the Cytoskeleton

Regulatory Level	Representative Molecules or Modifications	Main Role	Research Significance
Actin polymerization	Arp2/3, formin, profilin	Promotes F-actin network formation	Cell migration, membrane protrusion, phagocytosis, and cytokinesis
Actin depolymerization	Cofilin, gelsolin	Severs or depolymerizes F-actin	Cytoskeletal renewal and leading-edge dynamics
Actomyosin contraction	Myosin II, MLC, ROCK	Generates cellular contractile force	Stress fibers, rear retraction, and cellular mechanics
Microtubule stabilization	Acetylated tubulin, MAPs	Maintains stable microtubule structures	Neural axons, cilia, and intracellular transport
Microtubule destabilization	Stathmin, kinesin-13	Promotes microtubule depolymerization	Mitosis and remodeling of cell polarity
Intermediate filament reorganization	Vimentin phosphorylation, lamin phosphorylation	Regulates intermediate filament networks and nuclear membrane structure	Migration, division, and mechanical stress

3 Cytoskeleton and Signal Transduction

3.1 Structural Proteins Directly Participate in Signal Transmission

The cytoskeleton can participate in signal transduction by connecting signaling proteins, membrane receptors, and organelles. For example, the actin network can affect receptor clustering and endocytosis, microtubules can regulate transport of signaling complexes, and intermediate filaments can interact with kinases, phosphatases, and stress-related proteins.

(1) Spatial organization of receptors

Cell membrane receptors and adhesion molecules are often connected to the actin cortex. Changes in cytoskeletal structure can affect receptor clustering, internalization, recycling, and downstream signal intensity.

(2) Transport of signaling complexes

The microtubule system can transport signaling molecules, vesicles, and organelles, allowing signals to form spatial distributions inside cells. In neuronal axons, microtubule-dependent transport is important for synaptic function and neurodegenerative diseases.

3.2 The Cytoskeleton as a Signaling Scaffold

The cytoskeleton can act as a macromolecular scaffold that organizes multiple signaling molecules at specific locations, giving signal transduction spatial directionality. Focal adhesions, cell leading edges, spindles, and cell junction regions are all important sites for cytoskeleton-mediated signal integration.

(1) Focal adhesion signaling

After integrins bind to the extracellular matrix, they recruit molecules such as FAK, Src, Paxillin, Talin, and Vinculin, connect to the actin cytoskeleton, and activate signaling related to migration, survival, and mechanotransduction.

(2) Leading-edge signaling

Rac1, Cdc42, and PI3K regulate actin polymerization and membrane protrusion formation at the leading edge of migrating cells, enabling directional movement.

(3) Mechanotransduction signaling

Cells sense matrix stiffness, tensile force, and shear stress through actin stress fibers, focal adhesions, and the nuclear skeleton, thereby affecting pathways such as YAP/TAZ, RhoA/ROCK, FAK, and MAPK.

 

Figure 1 Schematic diagram of integrin-mediated cytoskeletal signaling

Table 3 Cytoskeleton-Related Signaling Nodes

Signaling Node	Main Cytoskeletal Association	Functional Output	Common Detection
RhoA/ROCK	Actin stress fibers, myosin contraction	Cell contraction, enhanced adhesion, mechanical response	RhoA activity, p-MLC, stress fibers
Rac1	Branched actin network, lamellipodia	Leading-edge extension, migration	Rac1 activity, lamellipodia, F-actin
Cdc42	Filopodia, cell polarity	Directional migration, polarity establishment	Cdc42 activity, filopodia, cell polarity markers
FAK/Src	Focal adhesions, actin linkage	Adhesion, migration, survival	p-FAK, p-Src, Paxillin
Paxillin	Focal adhesion scaffold	Focal adhesion assembly and turnover	Paxillin, p-Paxillin, focal adhesion area
PI3K/AKT	Leading edge, membrane lipid signaling	Cell migration, survival, polarity	p-AKT, PIP3 localization, migration assays
YAP/TAZ	Actin tension, nuclear skeleton	Mechanotransduction, proliferation, differentiation	YAP/TAZ nuclear localization, CTGF, CYR61

4 Cytoskeleton and Cell Migration

4.1 Basic Process of Cell Migration

Cell migration is a multistep process jointly driven by morphological changes, cell adhesion, cytoskeletal remodeling, and signal transduction. It participates in embryonic development, wound repair, immune cell patrol, angiogenesis, and tumor metastasis.

(1) Polarity establishment

Migrating cells first establish front-rear polarity. Rac1, Cdc42, PI3K, and actin polymerization signals are enriched at the leading edge, while RhoA/ROCK and myosin contraction signals are enriched at the rear.

(2) Leading-edge extension

Actin polymerizes at the leading edge to form lamellipodia or filopodia, allowing the cell membrane to extend toward the migration direction.

(3) Adhesion formation

Integrins mediate cell binding to the extracellular matrix and form focal adhesions through FAK, Paxillin, Talin, and Vinculin, transmitting external matrix signals to the cytoskeleton.

(4) Cell body translocation and rear retraction

Myosin II mediates actin contraction, moving the cell body forward while adhesions at the rear are released, completing one migration cycle.

4.2 Migration Modes

Cell migration is not a single mode. Depending on cell type, matrix environment, adhesion strength, and cytoskeletal state, cells can show mesenchymal migration, amoeboid migration, collective migration, or invasive migration.

Table 4 Cell Migration Modes and Cytoskeletal Features

Migration Mode	Cytoskeletal Features	Common Scenario	Key Detection
Mesenchymal migration	Obvious actin stress fibers and focal adhesions; integrin-dependent	Fibroblasts, tumor cell invasion	FAK/Paxillin, MMP, Transwell
Amoeboid migration	Weak adhesion; dependent on cortical actomyosin contraction	Immune cells, some tumor cells	p-MLC, RhoA/ROCK, cell morphology
Collective migration	Cell-cell junctions are retained; leader cells provide traction	Epithelial repair, collective invasion of cancer cells	E-cadherin, F-actin, leader cell markers
Neurite extension	Coordinated regulation by microtubules and actin in the growth cone	Neural development, axon regeneration	βIII-tubulin, GAP43, F-actin

4.3 Interpretation of Migration Assays

Cell migration assays should avoid misinterpreting proliferation, cell death, or matrix degradation as enhanced migration. Wound healing assays are suitable for observing population migration trends, but are easily affected by cell proliferation. Transwell assays are more suitable for chemotaxis analysis. Live-cell imaging can reflect migration speed, directionality, and morphological dynamics.

Table 5 Common Experiments in Cytoskeleton and Migration Research

Experiment Type	Main Use	Recommended Indicators	Interpretation Focus
Phalloidin staining	Observing F-actin structures	Stress fibers, pseudopodia, cortical actin	Should be combined with cell morphology and localization analysis
α/β-Tubulin staining	Observing microtubule networks	Microtubule arrangement, spindle, axonal microtubules	Fixation methods can affect microtubule structure
Vimentin/Keratin staining	Assessing intermediate filaments and cell state	Intermediate filament distribution, EMT status	Should be combined with cell type markers
Wound healing assay	Population migration	Wound closure rate	Cell proliferation should be controlled
Transwell assay	Chemotaxis and invasion	Number of migrated cells	In invasion assays, matrix degradation ability should be distinguished
Focal adhesion staining	Adhesion structure analysis	FAK, Paxillin, Vinculin	Focus on focal adhesion size, number, and turnover
Live-cell imaging	Dynamic migration analysis	Speed, directionality, trajectory	Can distinguish random migration from directional migration

5 Cytoskeleton in Cell Division and Intracellular Transport

5.1 Mitosis

Microtubules are the core structures of the mitotic spindle and are responsible for chromosome alignment, spindle checkpoint regulation, and sister chromatid separation. Actin and myosin participate in cytokinetic contractile ring formation, while intermediate filaments and lamins are reorganized during cell division.

(1) Microtubules and the spindle

Microtubule dynamic stability directly affects spindle formation and chromosome segregation. Both microtubule stabilizers and destabilizers can block mitosis and induce cell cycle arrest and cell death.

(2) Actomyosin contractile ring

During cytokinesis, actin and myosin II form a contractile ring, causing membrane ingression and completing separation into two daughter cells.

5.2 Intracellular Transport

Microtubules and actin together form intracellular transport tracks. Microtubules are mainly responsible for long-distance transport, while actin more often participates in transport near the cell cortex, membrane-proximal regions, and short-distance transport. Motor proteins such as kinesin, dynein, and myosin transport organelles, vesicles, protein complexes, and RNA to specific regions.

Table 6 Cytoskeleton-Related Functions in Cell Division and Transport

Process	Main Cytoskeletal Components	Key Molecules	Functional Significance
Spindle formation	Microtubules	α/β-Tubulin, Aurora, Kinesin	Chromosome alignment and segregation
Cytokinesis	Actin, Myosin II	F-actin, MLC, RhoA	Formation of the cellular contractile ring
Vesicle transport	Microtubules, Actin	Kinesin, Dynein, Myosin	Secretion, endocytosis, and membrane transport
Mitochondrial positioning	Microtubules, Actin	Miro, Milton, Dynein, Kinesin	Energy supply and cellular stress response
Axonal transport	Microtubules	Kinesin, Dynein, Tau	Neuronal function and neurodegenerative diseases

6 Cytoskeletal Abnormalities and Disease Mechanisms

6.1 Tumor Invasion and Metastasis

Tumor cell migration, invasion, and metastasis depend on cytoskeletal remodeling, focal adhesion turnover, and extracellular matrix degradation. During EMT, decreased E-cadherin, increased Vimentin, enhanced actin stress fibers, and altered cell adhesion patterns can all increase migratory and invasive capacity.

(1) Recommended detection

F-actin, Vimentin, E-cadherin, N-cadherin, p-FAK, Paxillin, RhoA/Rac1/Cdc42 activity, MMPs, and Transwell invasion assay.

(2) Interpretation focus

Enhanced migration does not equal enhanced metastasis. To support a metastatic mechanism, invasion, matrix degradation, intravasation/extravasation, in vivo metastasis models, or clinical tissue localization evidence should be combined.

6.2 Neurodegenerative Diseases

Neurons are highly dependent on microtubule stability and axonal transport. Tau abnormalities, microtubule depolymerization, motor protein transport defects, and abnormal neurofilament aggregation can all lead to impaired axonal transport, reduced synaptic function, and neuronal degeneration.

(1) Recommended detection

Acetylated tubulin, βIII-tubulin, Tau, p-Tau, Neurofilament, Kinesin, Dynein, mitochondrial transport, and axon length.

(2) Interpretation focus

Microtubule changes in neurons should be analyzed together with axonal transport and synaptic function. Microtubule function should not be judged only by changes in tubulin expression.

6.3 Cardiomyopathy, Myopathy, and Skin Diseases

Mutations in intermediate filaments and actin-related proteins can reduce tissue mechanical stability. Desmin abnormalities are associated with myopathy and cardiomyopathy, keratin abnormalities can cause epithelial mechanical fragility and blistering skin diseases, and lamin abnormalities can affect nuclear structure and tissue mechanics.

6.4 Inflammation, Fibrosis, and Immune Cell Function

Immune cell migration, phagocytosis, immune synapse formation, and inflammatory factor release all depend on cytoskeletal remodeling. During fibroblast activation and fibrosis, actin stress fibers, α-SMA, FAK, and RhoA/ROCK signaling are often significantly enhanced.

Table 7 Disease Directions Related to Cytoskeletal Abnormalities

Disease Direction	Key Cytoskeletal Change	Main Mechanism	Common Indicators
Tumor metastasis	Actin remodeling, focal adhesion turnover, increased Vimentin	Migration, invasion, EMT	F-actin, Vimentin, p-FAK, Transwell
Neurodegenerative diseases	Microtubule instability, Tau abnormalities, axonal transport defects	Synaptic injury, axonal degeneration	p-Tau, Acetylated tubulin, Neurofilament
Cardiomyopathy and myopathy	Abnormal Desmin or actin-related structures	Reduced mechanical support in muscle cells	Desmin, α-actinin, F-actin
Skin fragility diseases	Abnormal Keratin network	Reduced epithelial mechanical stability	Keratin, cell junction markers
Fibrosis	Enhanced actin stress fibers and α-SMA	Myofibroblast activation	α-SMA, F-actin, p-FAK, Collagen
Kidney and nuclear lamina disorders	Abnormal Lamin or podocyte cytoskeleton	Nuclear mechanics and podocyte structural injury	Lamin, Synaptopodin, Actin

7 Cytoskeleton-Targeted Intervention and Drug Research

7.1 Microtubule-Targeting Drugs

Microtubules are important targets of antitumor drugs. Microtubule stabilizers inhibit microtubule dynamics, while microtubule destabilizers promote microtubule depolymerization. Both types of drugs can interfere with spindle function and cause mitotic arrest.

(1) Microtubule stabilizers

Taxane drugs inhibit dynamic remodeling by stabilizing microtubule structures and are commonly used in studies of mitotic blockade and tumor cell death.

(2) Microtubule destabilizers

Colchicine, vinblastine, nocodazole, and related compounds can interfere with microtubule polymerization or promote microtubule depolymerization. They are commonly used to study microtubule dynamics, cell division, and intracellular transport.

7.2 Actin-Targeted Intervention

Inhibitors of actin polymerization or depolymerization can be used to analyze the roles of microfilaments in migration, phagocytosis, cytokinesis, and cell morphology maintenance. For example, cytochalasins, latrunculins, and jasplakinolide can interfere with actin network dynamics.

7.3 Targeting Cytoskeletal Regulatory Signaling

Signaling nodes such as RhoA/ROCK, FAK, Src, Paxillin, PI3K, and YAP/TAZ regulate cytoskeletal structure and cellular mechanical state. They are important intervention directions in studies of tumor invasion, fibrosis, inflammation, and vascular remodeling.

Table 8 Cytoskeleton-Targeted Intervention Directions

Intervention Direction	Representative Effect	Research Use	Key Interpretation
Microtubule stabilization	Enhances microtubule stability and inhibits dynamic changes	Mitotic blockade and antitumor mechanisms	Spindle abnormalities and cell cycle arrest
Microtubule destabilization	Inhibits microtubule polymerization or promotes depolymerization	Microtubule dynamics, intracellular transport, neural axon research	Microtubule network disruption and impaired transport
Actin polymerization inhibition	Inhibits F-actin formation or membrane protrusions	Migration, phagocytosis, cytokinesis research	Reduced F-actin and decreased migration
Actin stabilization	Excessively stabilizes F-actin	Validation of actin dynamics dependence	Cytoskeletal stiffening and abnormal migration
ROCK inhibition	Reduces actomyosin contraction	Cellular mechanics, fibrosis, stem cell culture	Decreased p-MLC and reduced stress fibers
FAK/Src inhibition	Blocks focal adhesion signaling	Tumor migration, invasion, and adhesion research	Reduced p-FAK/p-Src and inhibited migration
Tubulin acetylation regulation	Alters the proportion of stable microtubules	Neural transport, cilia, and microtubule stability research	Changes in acetylated tubulin

8 Representative Products Related to Cytoskeleton Research

Research Module	Representative Product	CAS No.	Mechanism or Detection Positioning	Applicable Research
F-actin structure observation	Phalloidin	17466-45-4	Binds F-actin and is used for actin filament labeling	F-actin staining, stress fibers, pseudopodia, and cell morphology observation
Actin polymerization inhibition	Cytochalasin D	22144-77-0	Inhibits actin polymerization and disrupts F-actin dynamics	Cell migration, cytokinesis, phagocytosis, and microfilament function validation
Migration/invasion mechanism research	Cytochalasin B	14930-96-2	Disrupts actin polymerization and cytoskeletal dynamics	Cell migration, phagocytosis, membrane protrusions, and glucose transport-related research
Actin polymerization inhibition	Latrunculin A	76343-93-6	Binds G-actin and blocks actin polymerization	Microfilament depolymerization, cell morphology changes, and migration mechanism research
Actin polymerization inhibition	Latrunculin B	76343-94-7	Interferes with G-actin incorporation into F-actin	Actin dynamics, cytoskeletal remodeling, and cell migration research
Actin stabilization intervention	Jasplakinolide	102396-24-7	Stabilizes F-actin and promotes actin polymerization	Microfilament stability, cytoskeletal stiffening, and abnormal migration research
Myosin II contraction regulation	Blebbistatin	856925-71-8	Myosin II ATPase inhibitor	Actomyosin contraction, cellular mechanics, rear retraction, and cytokinesis research
Microtubule stabilization intervention	Paclitaxel	33069-62-4	Microtubule stabilizer that inhibits microtubule dynamics	Mitotic arrest, spindle abnormalities, and antitumor mechanism research
Microtubule destabilization intervention	Nocodazole	31430-18-9	Interferes with microtubule polymerization and promotes microtubule network disruption	M-phase synchronization, microtubule dynamics, intracellular transport, and spindle research
Microtubule destabilization intervention	Colchicine	64-86-8	Binds tubulin and inhibits microtubule polymerization	Microtubule depolymerization, cell division arrest, and inflammation-related research
Microtubule destabilization intervention	Vinblastine sulfate	143-67-9	Inhibits microtubule polymerization	Spindle disruption, mitotic arrest, and anti-mitotic drug efficacy research
Microtubule destabilization intervention	Vincristine sulfate	2068-78-2	Microtubule polymerization inhibitor	Microtubule dynamics, tumor cell mitotic arrest, and neurotoxicity research
Microtubule dynamics regulation	Demecolcine	477-30-5	Inhibits microtubule formation	Chromosome segregation, cell cycle arrest, and microtubule function research
ROCK signaling inhibition	Y-27632	146986-50-7	ROCK inhibitor that reduces actomyosin contraction	Cell tension, stress fibers, stem cell culture, and migration research
ROCK signaling inhibition	Fasudil hydrochloride	105628-07-7	ROCK-related pathway inhibitor	RhoA/ROCK signaling, vascular response, fibrosis, and cell contraction research
FAK adhesion signaling research	PF-573228	869288-64-2	FAK inhibitor	Focal adhesion signaling, p-FAK, cell migration, and invasion research
FAK adhesion signaling research	PF-562271	717907-75-0	FAK/Pyk2 inhibitor	Integrin-FAK signaling, tumor migration, invasion, and adhesion research
Src/FAK crosstalk signaling research	PP2	172889-26-8	Src family kinase inhibitor	Src-FAK axis, focal adhesion turnover, migration, and invasion mechanism research
PI3K leading-edge signaling research	LY294002	154447-36-6	PI3K inhibitor	PI3K/AKT signaling, cell polarity, migration, and survival research
Microtubule acetylation regulation	Trichostatin A	58880-19-6	HDAC inhibitor that can affect tubulin acetylation-related status	Acetylated tubulin, microtubule stability, neural axons, and cilia research

9 Cytoskeleton-Related Product Lines and Application Directions

Product Line Direction	Research Positioning	Main Applications
Annexin A	Proteins related to membrane-cytoskeleton linkage, membrane repair, and membrane structural remodeling	Cell membrane dynamics, vesicle transport, inflammatory responses, and membrane injury repair research
Arp2/3 complex	Actin branch nucleation complex	Lamellipodia formation, cell migration, phagocytosis, and membrane protrusion research
Dynamin	Dynamin-related membrane scission and endocytosis regulatory proteins	Receptor endocytosis, vesicle release, membrane transport, and cytoskeleton-membrane dynamics research
gap junction protein	Proteins related to intercellular communication and junction structures	Cell junctions, tissue synchronization, coordinated migration, and inflammatory signal propagation research
Integrin	Cell-matrix adhesion receptors	Focal adhesion formation, FAK/Src signaling, migration, invasion, and mechanotransduction research
kinesin	Microtubule motor proteins	Vesicle transport, chromosome movement, axonal transport, and organelle positioning research
lysyl oxidase	Enzymes regulating extracellular matrix crosslinking and tissue mechanics	ECM stiffening, fibrosis, tumor invasion, and mechanical microenvironment research
MARCKS	Actin-binding and membrane phospholipid regulatory protein	Cell migration, membrane cytoskeleton regulation, secretion, and inflammation-related research
MASTL	Mitotic regulatory kinase	Cell cycle, spindle regulation, mitotic progression, and tumor proliferation research
Microtubules/tubulins	Core components of microtubule structure	Microtubule networks, spindle, intracellular transport, neural axons, and microtubule drug research
Mps1	Spindle assembly checkpoint kinase	Chromosome alignment, spindle checkpoint, mitotic errors, and antitumor mechanism research
myosin	Actin-related motor proteins	Actomyosin contraction, cytokinesis, cell migration, and cellular mechanics research
PAK	Downstream effector kinase of Rho GTPases	Rac/Cdc42 signaling, cytoskeletal remodeling, cell migration, and tumor invasion research
ROCK	RhoA downstream contraction-regulating kinase	Stress fibers, p-MLC, cell contraction, fibrosis, and mechanotransduction research

10 Common Questions in Cytoskeleton Research

10.1 Does Increased F-actin Always Indicate Enhanced Migration?

Not necessarily. Increased F-actin may indicate enhanced stress fibers, increased cell contraction, or cytoskeletal stiffening, and does not necessarily mean increased migratory capacity. Enhanced migration should be judged together with leading-edge structures, focal adhesion turnover, migration speed, and Transwell results.

10.2 Does Increased Tubulin Expression Mean Microtubules Are More Stable?

Not necessarily. Total tubulin only reflects protein expression level. Microtubule stability is more appropriately evaluated by acetylated tubulin, detyrosinated tubulin, microtubule network morphology, and dynamic imaging.

10.3 Is Increased Vimentin Equivalent to EMT?

No. Vimentin is one of the markers of a mesenchymal phenotype, but EMT should be evaluated together with decreased E-cadherin, increased N-cadherin, transcription factor changes, morphological changes, and enhanced migration and invasion.

10.4 Can Cell Migration Be Studied Only with a Wound Healing Assay?

It is not recommended. Wound healing assays are easily affected by cell proliferation, cell death, and scratch width. To prove changes in chemotaxis or invasion ability, Transwell, matrix invasion, or live-cell imaging assays should be added.

10.5 Is Cell Death Induced by Microtubule Drugs Only Due to Microtubule Disruption?

Not necessarily. Microtubule drugs can induce mitotic arrest, DNA damage response, mitochondrial stress, and apoptosis. Interpretation should combine cell cycle analysis, spindle morphology, caspase activation, and cell death indicators.

Cytoskeleton research should comprehensively analyze structural components, dynamic regulation, the mechanical environment, and signaling networks. Microfilaments, microtubules, and intermediate filaments respectively participate in morphology changes, intracellular transport, cell division, and mechanical support, and connect cell migration, proliferation, differentiation, and disease progression through nodes such as Rho GTPases, FAK/Paxillin, PI3K, ROCK, and YAP/TAZ.

For more related articles, please see below:

[1] Cytoskeletal Staining Reagents