Main Methods and Experimental Selection for Microfilament Staining

Microfilaments are mainly formed by the polymerization of actin and are an important component of the cytoskeleton. They participate in the maintenance of cell morphology, adhesion and migration, cytokinesis, endocytic transport, stress fiber formation, and the establishment of cell polarity. The purpose of microfilament staining is not merely to outline cell morphology, but to specifically label F-actin, total actin, or dynamically polymerized structures, thereby enabling analysis of cytoskeletal rearrangement, changes in cell state, and morphological responses after external stimulation.

Keywords: microfilament staining; F-actin; actin; phalloidin; immunofluorescence; live-cell imaging; cytoskeleton; stress fibers; cell migration; super-resolution imaging

1、Basic Logic of Microfilament Staining

1.1 Detection targets of microfilament staining

(1) F-actin

F-actin is polymerized actin and is the core target in microfilament staining. Intracellular structures such as stress fibers, cortical actin, pseudopodia, lamellipodia, filopodia, and the cytokinetic ring all depend on the spatial organization of F-actin.

(2) G-actin

G-actin is monomeric actin and usually does not form clearly visible filamentous structures. Most routine microfilament staining methods preferentially label F-actin rather than G-actin. If the experimental goal is to distinguish polymerized actin from monomeric actin, specific probes, biochemical fractionation, or polymerization/depolymerization controls are required.

(3) Total actin

Total actin includes both F-actin and G-actin, and may also include different actin isoforms. Antibody-based methods are usually more suitable for detecting specific actin isoforms or total actin expression, but their ability to resolve filamentous structures is generally weaker than phalloidin-based F-actin staining.

1.2 Principles for method selection

(1) Phalloidin is preferred for fixed samples

For fixed cells, tissue sections, or routine immunofluorescence experiments, fluorescently labeled phalloidin is a commonly used method for visualizing F-actin. It provides strong signal, low background, and clear filamentous structures, making it suitable for observing cytoskeletal morphology and stress fibers.

(2) Antibody staining is preferred for protein expression and localization

If the target of interest is a microfilament-associated protein such as β-actin, α-SMA, γ-actin, cortactin, or α-actinin, immunofluorescence staining should be selected. Antibody-based methods are suitable for expression localization and isoform analysis, but they should not be simply equated with analysis of F-actin polymerization status.

(3) Live-cell probes are preferred for dynamic processes

If microfilament formation, disappearance, rearrangement, or changes at the migration front need to be observed, live-cell labeling strategies such as LifeAct, Utrophin-ABD, F-tractin, or SiR-actin should be selected. These methods are better suited for dynamic imaging, but probe interference with the actin cytoskeleton itself must be carefully controlled.

Table 1 Basic Classification of Microfilament Staining Methods

Method type	Representative method	Main target	Applicable sample	Core application
Phalloidin staining	FITC/Rhodamine/Alexa Fluor-phalloidin	F-actin	Fixed cells, tissue sections	Visualization of microfilament structures and stress fibers
Antibody immunofluorescence	Anti-actin, anti-β-actin, anti-α-SMA	Total actin or specific isoforms	Fixed cells, tissue sections	Expression localization and isoform analysis
Live-cell protein probes	LifeAct, Utrophin-ABD, F-tractin	Live-cell F-actin	Live cells	Dynamic rearrangement, migration, and cytokinesis observation
Small-molecule live-cell probes	SiR-actin, SPY-actin-type probes	Live-cell F-actin	Live cells	Live-cell microfilament imaging and long-term observation
Transgenic fusion proteins	GFP-actin, mCherry-actin	Labeled actin pool	Live cells	Dynamic expression and cytoskeletal remodeling observation
Super-resolution staining	Fluorescent phalloidin, optimized fluorescent antibodies	Fine F-actin structures	Mainly fixed cells	Analysis of microfilament bundles, cortical networks, and protrusive structures

2、Phalloidin Staining

2.1 Method principle

(1) Specific binding to F-actin

Phalloidin specifically binds F-actin and does not mainly bind G-actin. Fluorescently labeled phalloidin can directly visualize polymerized microfilament structures; therefore, it is widely used to observe stress fibers, cortical actin at the cell edge, and structures at the migration front.

(2) Types of fluorescent labels

Common fluorescent labels include FITC, TRITC, rhodamine, Alexa Fluor 488, Alexa Fluor 555, Alexa Fluor 568, Alexa Fluor 594, and Alexa Fluor 647. Selection should be based on microscope channels, antibody fluorescence combinations, and nuclear counterstain channels.

(3) Advantages in fixed samples

Phalloidin is generally used in fixed and permeabilized samples. After fixation, membrane permeability increases, allowing the probe to enter cells and bind F-actin, generating clear filamentous signals.

2.2 Experimental workflow

(1) Fixation

4% paraformaldehyde is commonly used for fixation because it preserves cell morphology and microfilament structures well. Methanol fixation may disrupt some F-actin structures and is not the preferred choice for routine phalloidin staining.

(2) Permeabilization

Triton X-100 or saponin can be used for membrane permeabilization. Excessive permeabilization may damage cell-edge structures, while insufficient permeabilization may prevent adequate probe entry.

(3) Staining

Fluorescent phalloidin is usually incubated under light-protected conditions. Staining concentration and incubation time should be optimized according to probe instructions. Excessive probe concentration increases background, whereas insufficient concentration leads to weak microfilament signals.

(4) Mounting

Fluorescent samples should be mounted using an anti-fade mounting medium and stored away from light. If nuclear localization is required, DAPI, Hoechst, or DRAQ5 can be used for nuclear counterstaining.

2.3 Application scenarios

(1) Cell morphology analysis

Phalloidin staining clearly shows cell spreading area, cell edges, stress fiber number, and microfilament orientation. It is suitable for experiments involving cell adhesion, migration, mechanical stimulation, and drug treatment.

(2) Cytoskeletal rearrangement

When cells are affected by RhoA/ROCK, Rac1, Cdc42, TGF-β, inflammatory factors, or changes in matrix stiffness, F-actin often undergoes prominent rearrangement. Phalloidin staining is one of the preferred methods for observing these changes.

(3) Cell division and contractile structures

In studies of cytokinesis, contractile ring formation, cell contraction, and epithelial barrier changes, F-actin localization reflects cellular mechanical state and cytoskeletal organization.

Table 2 Applicable Scenarios and Interpretation Points for Phalloidin Staining

Application scenario	Main structures observed	Interpretation points	Notes
Cell spreading	Cell edges, stress fibers	Cell area, fiber density, and orientation	Plating density and culture time must be standardized
Cell migration	Lamellipodia, filopodia	F-actin enrichment at the leading edge and polarity	Fixation time affects preservation of dynamic structures
EMT/fibrosis	Stress fibers, α-SMA-related structures	Enhanced fiber bundles and cell elongation	Can be combined with α-SMA immunofluorescence
Cytotoxicity	Microfilament breakage, collapse, aggregation	Cytoskeletal integrity and cell-edge changes	Death-cell artifacts should be excluded
Cytokinesis	Contractile ring	F-actin enrichment at the cleavage furrow	Appropriate cell-cycle stages must be captured
Barrier function	Cortical actin, junction-associated microfilaments	Continuity of cell boundaries	Can be combined with ZO-1, E-cadherin, and other markers

3、Antibody Immunofluorescence

3.1 Method principle

(1) Detection of total actin

Anti-actin antibodies can recognize intracellular actin and are suitable for observing total actin expression and localization. Because antibodies may recognize actin in different states, the results cannot be fully equated with F-actin polymerized structures.

(2) Detection of actin isoforms

Antibodies against α-SMA, β-actin, γ-actin, and other isoforms can be used to distinguish different cell types or functional states. For example, α-SMA is commonly used as a marker of myofibroblasts, vascular smooth muscle cells, and fibrosis-associated cells.

(3) Co-staining of microfilament regulatory proteins

Proteins such as cortactin, CAPG, and α-actinin can reflect actin branching, bundling, migration front formation, and stress fiber-associated structures. These antibodies are often combined with F-actin probes to analyze mechanisms of microfilament rearrangement.

3.2 Experimental workflow

(1) Fixation and permeabilization

Antibody staining usually requires fixation, permeabilization, and blocking. Fixation conditions affect antigen epitope preservation. Paraformaldehyde fixation is suitable for most cytoskeleton-related antibodies, while methanol fixation is suitable for some antibodies but may affect F-actin structures.

(2) Blocking

Blocking solution reduces nonspecific binding. Common choices include BSA, normal serum, or commercial blocking buffers. If background is high, the blocking system, antibody dilution, and washing conditions should be optimized.

(3) Primary and secondary antibody incubation

The primary antibody determines specificity, while the secondary antibody determines fluorescence intensity and channel selection. In multiplex staining, host species conflicts and spectral crosstalk should be avoided. Directly labeled antibodies can reduce the need for secondary antibodies and are suitable for multicolor co-staining or simplified workflows.

3.3 Method characteristics

(1) Advantages

Antibody-based methods can detect specific actin isoforms and are suitable for studying cell differentiation, myofibroblast activation, smooth muscle phenotype, tumor stromal activation, and tissue remodeling.

(2) Limitations

Antibody-based methods usually do not visualize F-actin filamentous structures as clearly as phalloidin. If the experimental question concerns microfilament bundle arrangement and polymerization status, phalloidin is still more direct.

(3) Complementary application

Phalloidin visualizes F-actin structure, whereas antibody methods visualize actin isoforms or related regulatory proteins. Combining the two helps distinguish “structural rearrangement” from “expression change.”

Table 3 Comparison Between Phalloidin Staining and Antibody Immunofluorescence

Comparison item	Phalloidin staining	Antibody immunofluorescence
Main target	F-actin	Total actin or specific actin isoforms
Structural visualization	Strong, with clear filamentous structures	Depends on antibody and fixation conditions
Suitable for isoform analysis	No	Yes
Operational complexity	Relatively low	Relatively high
Live-cell applicability	Not routinely applicable	Not routinely applicable
Co-staining with other markers	Easy	Requires consideration of antibody host and channels
Typical application	Microfilament structure, stress fibers, cell edges	α-SMA, β-actin, cell type, and expression localization

4、Live-Cell Microfilament Staining and Dynamic Imaging

4.1 Genetically encoded probes

(1) LifeAct

LifeAct is a commonly used F-actin-binding short peptide that can be fused to fluorescent proteins for dynamic observation of microfilaments in live cells. Its advantages include relatively uniform signal and limited interference with cell morphology, although high expression may still affect actin dynamics.

(2) Utrophin-ABD

The actin-binding domain of utrophin can be used to label F-actin and is often used in live-cell or developmental biology imaging. Compared with LifeAct, it has different binding characteristics and structural visualization performance, and should be optimized according to cell type.

(3) F-tractin

F-tractin can label F-actin structures and is suitable for dynamic observation of cell migration, protrusion formation, and cytoskeletal rearrangement. The risk of overexpression should still be controlled through low-expression vectors or stable expression screening.

4.2 Fluorescent protein-labeled actin

(1) GFP-actin

GFP-actin directly reports the distribution and dynamic changes of actin in cells. It is suitable for long-term live-cell imaging and cytoskeletal remodeling studies.

(2) Expression interference

Exogenous actin fusion proteins may alter endogenous actin polymerization and depolymerization, as well as interactions with actin-binding proteins. When expression is too high, cell morphology and microfilament dynamics may deviate from the true state.

(3) Control setup

When GFP-actin is used, untransfected controls, empty-vector controls, and low-expression screening conditions should be included. When possible, results should be cross-validated with fixed-sample phalloidin staining.

4.3 Small-molecule live-cell probes

(1) SiR-actin

SiR-actin is a small-molecule probe for live-cell microfilament imaging and is commonly used in the far-red channel. Its advantage is that it does not require transfection, making it suitable for some hard-to-transfect cells and short-term dynamic imaging.

(2) SPY-actin-type probes

SPY555-actin, SPY650-actin, and related probes can be used for F-actin imaging in live or fixed samples. Probes in different channels can be selected according to multicolor imaging schemes and are suitable for combination with nuclear staining, mitochondrial labeling, or fluorescently labeled target proteins.

(3) Application boundaries

Live-cell probes are suitable for observing dynamic processes, but they should not be used for precise quantification of total F-actin without validation. In drug screening or long-term imaging, the effects of probes on cell migration, proliferation, and morphology should be evaluated.

Table 4 Comparison of Live-Cell Microfilament Labeling Methods

Method	Labeling target	Advantages	Main limitations
LifeAct fluorescent protein	Dynamic F-actin structures	Mature expression constructs, suitable for dynamic observation	High expression may interfere with microfilament dynamics
Utrophin-ABD fluorescent protein	F-actin	Relatively stable structural visualization	Requires transfection or stable cell line construction
F-tractin fluorescent protein	F-actin	Suitable for migration and morphological dynamics	Expression level must be strictly controlled
GFP-actin	Labeled actin pool	Allows observation of overall actin dynamics	Exogenous actin may affect the endogenous system
SiR-actin	Live-cell F-actin	No transfection required; far-red imaging	Excessive concentration may affect microfilament dynamics
SPY-actin-type probes	F-actin in live or fixed samples	Flexible channel selection, suitable for multicolor imaging	Concentration and incubation time must be optimized

5、Microfilament Staining in Tissue Samples

5.1 Frozen sections

(1) Applicability

Frozen sections are relatively suitable for preserving some cytoskeletal structures and antigen activity. They can be used for phalloidin staining or actin-related immunofluorescence. They are suitable for observing microfilaments or actin-related structures in muscle tissue, epithelial tissue, vascular tissue, and tumor tissue.

(2) Fixation conditions

Frozen sections can be fixed with paraformaldehyde, or acetone/methanol can be selected according to antibody requirements. If the target is F-actin structure, overly strong organic solvent treatment should generally be avoided to prevent microfilament disruption.

(3) Background control

Tissue samples often show more obvious autofluorescence, nonspecific binding, and thickness differences. Negative controls, no-primary-antibody controls, and appropriate channel combinations are required.

5.2 Paraffin sections

(1) Immunohistochemistry and immunofluorescence

Paraffin sections are more commonly used for detecting actin isoforms by antibody staining, such as α-SMA for smooth muscle, vascular walls, or myofibroblasts. Because paraffin processing may affect F-actin structures, phalloidin staining in paraffin sections is usually less stable than in cell coverslip samples.

(2) Antigen retrieval

Actin-related antibodies may require heat-induced or enzymatic antigen retrieval on paraffin sections. Overly strong retrieval can increase tissue background, while insufficient retrieval may result in weak signal.

(3) Tissue structure interpretation

Actin positivity in tissues does not necessarily indicate microfilament structural rearrangement; it may also reflect smooth muscle, myofibroblasts, or vascular components. Interpretation should be based on tissue location and cell morphology.

Table 5 Selection of Microfilament-Related Staining in Tissue Samples

Sample type	Recommended method	Main observation content	Interpretation points
Cell coverslips	Phalloidin staining	F-actin, stress fibers, cell edges	Most suitable for microfilament structure observation
Spheroids/organoids	Phalloidin, anti-actin immunofluorescence	Cortical actin, cell polarity	Probe penetration depth must be considered
Frozen sections	Phalloidin, α-SMA immunofluorescence	Microfilament distribution and actin-related structures	Control autofluorescence and section thickness
Paraffin sections	α-SMA, β-actin, and related antibodies	Smooth muscle, myofibroblasts, tissue structure	More suitable for expression localization than fine F-actin networks
Muscle tissue	Actin-related antibodies, phalloidin	Muscle fiber structure and cytoskeleton	Distinguish sarcomeric structures from ordinary microfilament networks
Vascular tissue	α-SMA, F-actin-related staining	Smooth muscle layer and vascular wall structure	Should be interpreted together with elastic fiber or endothelial markers

6、Super-Resolution and High-Content Microfilament Imaging

6.1 Super-resolution imaging

(1) Applicable methods

STED, SIM, STORM/PALM, and other super-resolution imaging methods can be used to observe fine structures such as microfilament bundles, cortical actin networks, filopodia, and cell junction regions. Fluorescent phalloidin and highly photostable probes are commonly used for fixed-sample super-resolution imaging.

(2) Dye selection

Super-resolution imaging requires high dye brightness, photostability, and labeling density. Far-red or highly photostable dyes are usually more suitable for long exposure and high-power excitation.

(3) Sample preparation

Fixation quality, background fluorescence, mounting medium, and refractive index matching significantly affect imaging resolution. Microfilament structures are fine and dense, and improper preparation can easily cause artificial breaks or filament fusion.

6.2 High-content analysis

(1) Quantitative indicators

High-content imaging can quantify cell area, F-actin intensity, stress fiber orientation, cell circularity, edge roughness, nuclear-to-cytoplasmic ratio, and cell-population heterogeneity.

(2) Image segmentation

Microfilament staining is often used to identify cell boundaries, but in high-density cells or strong stress fiber backgrounds, relying only on F-actin for segmentation may be unstable. Combining nuclear staining and membrane markers can improve segmentation quality.

(3) Batch control

High-content experiments require standardized fixation time, staining concentration, exposure parameters, image thresholds, and well layout. When comparing across batches, positive and negative treatment controls should be included.

Table 6 Common Quantitative Indicators in Microfilament Staining

Quantitative indicator	Main meaning	Applicable method	Notes
Total F-actin fluorescence intensity	Overall microfilament signal level	Phalloidin, high-content imaging	Affected by exposure and cell area
Stress fiber density	Abundance of fiber bundles	Phalloidin, super-resolution imaging	Threshold and algorithm must be standardized
Fiber orientation	Consistency of microfilament alignment	Image analysis, directionality analysis tools	Sensitive to cell morphology and imaging angle
Cell spreading area	Cell adhesion and morphological changes	Phalloidin combined with nuclear staining	High-density cells are difficult to segment
Cell-edge F-actin enrichment	Changes at migration front or cortical actin	Phalloidin, LifeAct	Edge region must be clearly defined
Filopodia number	Cell migration and exploratory capacity	High-resolution or super-resolution imaging	Fine structures are limited by resolution
Perinuclear microfilament distribution	Changes related to cell tension and nuclear morphology	Phalloidin combined with nuclear staining	Focal plane differences must be distinguished

7、Product Selection for Microfilament Staining

Table 7 Reagent and Material Selection for Microfilament Staining

Cat. No.	Product Name	Grade/Purity/Specification	Product Category	Related Staining Method	Methodological Application Positioning
A743602	Actin-Tracker Red-555		F-actin fluorescent probe	Microfilament fluorescence staining	Directly used to visualize F-actin/microfilament structures; suitable for observing stress fibers, cortical actin, and the cell-edge cytoskeleton
A743603	Actin-Tracker Red-594		F-actin fluorescent probe	Microfilament fluorescence staining	Directly used for red-channel F-actin imaging; suitable for combination with green antibody signals or blue nuclear staining
A743604	Actin-Tracker Red-Rhodamine		F-actin fluorescent probe	Microfilament fluorescence staining	Can be used to observe microfilaments, stress fibers, and cytoskeletal rearrangement in fixed cells
M1511591	Microfilament Staining Solution (R250 Method)	BioReagent, Biological Stain, for microscopy	Conventional microfilament staining solution	R250 microfilament staining	Used to visualize stress fibers formed by microfilaments in adherent cells; suitable for observing cell spreading, stress fiber distribution, and cytoskeletal morphology under a conventional optical microscope.
Ab327504	Actin Beta Mouse mAb	KO Validation	β-actin antibody	Actin immunofluorescence/immunostaining	Used for β-actin expression localization; not equivalent to visualization of F-actin polymerized structures
Ab155822	beta Actin Mouse mAb	Carrier Free,ExactAb™,Azide Free,Validated,High Performance,PBS Only,See COA	β-actin antibody	Actin immunofluorescence/immunostaining	Suitable for β-actin localization or co-staining analysis; used to distinguish actin expression from microfilament structural changes
Ab090999	Recombinant beta Actin Antibody	ExactAb™, Validated, Recombinant, High Performance, See COA	β-actin recombinant antibody	Actin immunofluorescence/immunostaining	Can be used for total β-actin expression localization and cytoskeleton-related immunostaining
Ab327444	Recombinant Actin Beta Antibody	KD Validation	β-actin recombinant antibody	Actin immunofluorescence/immunostaining	Used for β-actin expression localization or method validation; suitable as an antibody-based microfilament-related detection item
Ab219181	beta Actin Mouse mAb (AF405)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled β-actin antibody	Direct immunofluorescence staining	Labels β-actin in the AF405 channel and is suitable for multicolor imaging without a secondary antibody
Ab219182	beta Actin Mouse mAb (AF488)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled β-actin antibody	Direct immunofluorescence staining	Labels β-actin in the AF488 channel and is suitable for combination with red microfilament probes or red nuclear/membrane markers
Ab219184	beta Actin Mouse mAb (AF555)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled β-actin antibody	Direct immunofluorescence staining	AF555-channel β-actin localization; suitable for multicolor immunofluorescence
Ab219186	beta Actin Mouse mAb (AF647)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled β-actin antibody	Direct immunofluorescence staining	Far-red β-actin labeling; suitable for samples with high tissue background or multicolor imaging
Ab176323	beta Actin Mouse mAb (TRITC)	ExactAb™, Validated, Azide Free, Ex:557nm, Em:576nm, 0.5 mg/mL	Fluorescently labeled β-actin antibody	Direct immunofluorescence staining	TRITC-channel β-actin labeling; suitable for routine fluorescence microscopy
Ab175850	beta Actin Mouse mAb (Biotin)	ExactAb™, High Performance, Validated, Azide Free, 1.0 mg/mL	Biotin-labeled β-actin antibody	Actin immunostaining/signal amplification	Can be used in β-actin immunostaining systems and is suitable for streptavidin-based signal amplification
Ab187009	alpha-Smooth Muscle Actin Mouse mAb	Carrier Free,ExactAb™,Azide Free,Validated,High Performance,PBS Only,≥95%(SDS-PAGE),1.0 mg/mL	α-SMA antibody	α-SMA immunofluorescence/immunostaining	Used for analysis of smooth muscle cells, myofibroblasts, and fibrosis-related microfilament phenotypes
Ab088443	alpha-Smooth Muscle Actin Mouse mAb	Carrier Free, ExactAb™, Validated, High Performance, See COA	α-SMA antibody	α-SMA immunofluorescence/immunostaining	Used for α-SMA expression localization; suitable for combination with F-actin probes to distinguish myofibroblast-like phenotypes
Ab325862	Recombinant Alpha Smooth Muscle Actin Antibody	KD Validation	α-SMA recombinant antibody	α-SMA immunofluorescence/immunostaining	Can be used for α-SMA localization and method validation; suitable for microfilament-related fibrosis experiments
Ab325877	Recombinant Alpha Smooth Muscle Actin Antibody	KD Validation	α-SMA recombinant antibody	α-SMA immunofluorescence/immunostaining	Used for α-SMA immunostaining and helps determine smooth muscle-like or myofibroblast-like cytoskeletal phenotypes
Ab219208	alpha-Smooth Muscle Actin Mouse mAb (AF405)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled α-SMA antibody	Direct immunofluorescence staining	Direct AF405-channel α-SMA labeling; suitable for multicolor co-staining systems
Ab219211	alpha-Smooth Muscle Actin Mouse mAb (AF488)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled α-SMA antibody	Direct immunofluorescence staining	Direct AF488-channel α-SMA labeling; can be paired with red F-actin probes
Ab219223	alpha-Smooth Muscle Actin Mouse mAb (Cy3)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled α-SMA antibody	Direct immunofluorescence staining	Cy3-channel α-SMA localization; suitable for observing myofibroblast activation and stress fiber-related phenotypes
Ab219225	alpha-Smooth Muscle Actin Mouse mAb (Cy5)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled α-SMA antibody	Direct immunofluorescence staining	Cy5 far-red α-SMA localization; suitable for multicolor tissue or cell imaging
Ab219226	alpha-Smooth Muscle Actin Mouse mAb (TRITC)	ExactAb™, Validated, 0.5 mg/mL	Fluorescently labeled α-SMA antibody	Direct immunofluorescence staining	Direct TRITC-channel α-SMA labeling; suitable for routine fluorescence microscopy
Ab088433	Recombinant Alpha Skeletal Muscle Actin Antibody	Recombinant, ExactAb™, Validated, High Performance, See COA	Skeletal muscle actin antibody	Actin isoform immunostaining	Suitable for localization of skeletal muscle actin isoforms in muscle tissue or myogenic cells
Ab104668	gamma Actin Antibody	ExactAb™, Validated, Carrier Free, 2.0 mg/mL	γ-actin antibody	Actin isoform immunostaining	Used for γ-actin localization and expression analysis; suitable as an actin isoform staining item
Ab087281	Actin Regulatory Protein CAPG/MCP Mouse mAb	ExactAb™, Validated, Carrier Free, 1.0 mg/mL	Microfilament regulatory protein antibody	Actin regulatory protein immunostaining	CAPG/MCP is an actin regulatory protein and can be used to analyze regulatory structures related to microfilament rearrangement
Ab334429	Actin Regulatory Protein CAPG/MCP Mouse mAb	PBS Only,See COA	Microfilament regulatory protein antibody	Actin regulatory protein immunostaining	Used for localization of actin regulatory proteins and suitable as a supporting antibody for microfilament rearrangement mechanism analysis
Ab327254	Recombinant Cortactin Antibody	KD Validation	Cortactin antibody	Microfilament-related structure immunostaining	Cortactin participates in actin branching and migration-front structures; suitable for studies of protrusions, migration, and cortical actin
Ab097390	Recombinant Cortactin Antibody	ExactAb™, Validated, Recombinant, 0.1 mg/mL	Cortactin antibody	Microfilament-related structure immunostaining	Used for cortactin localization; suitable for combination with F-actin probes to analyze cell migration and actin rearrangement
Ab325775	Recombinant Actinin Alpha 4 Antibody	KO Validation	α-Actinin 4 antibody	Microfilament-related structure immunostaining	α-Actinin participates in actin fiber bundle crosslinking and can be used for analysis of stress fibers and adhesion-related structures
Ab126469	Recombinant Sarcomeric Alpha Actinin Antibody	ExactAb™, Validated, Recombinant, 0.3 mg/mL	Sarcomeric α-actinin antibody	Muscle tissue/sarcomeric structure immunostaining	Suitable for localization of sarcomeric actin-related structures in muscle cells or muscle tissue
D266292	DRAQ5 Fluorescent Probe		Nuclear counterstaining probe	Nuclear counterstaining with microfilament staining	Does not label microfilaments; used for nuclear localization, cell counting, and multicolor imaging support
A131295	7-Aminoactinomycin D	Moligand™, ≥97%(HPLC)	Cell-state auxiliary dye	Auxiliary staining in microfilament injury/cytotoxicity experiments	Does not show microfilaments; identifies cells with compromised membrane integrity and helps avoid misinterpreting death-related cytoskeletal collapse as specific microfilament rearrangement
F1508973	Fischor Mounting Medium	BioReagent,for microscopy,Suitable for Immunofluorescence(IF),Suitable for Immunohistochemistry(IHC)	Mounting material	Mounting after microfilament fluorescence staining	Used for mounting and preservation after microfilament immunofluorescence or probe staining
A752105	Enhanced Antifade Mounting Medium	BioReagent, for fluorescence analysis, Suitable for Immunofluorescence(IF)	Anti-fade mounting medium	Mounting after fluorescent microfilament staining	Used to reduce photobleaching of Actin-Tracker or fluorescent antibody signals
A598329	Antifluorescent quencher		Anti-fade mounting medium	Mounting after fluorescent microfilament staining	Used to preserve signal after F-actin fluorescence staining or actin immunofluorescence
C1508971	Routine Glycerol Mounting Medium	BioReagent,for microscopy,Suitable for Immunofluorescence(IF),for fluorescence analysis	Mounting material	Mounting after microfilament fluorescence staining	Suitable for mounting microfilament-stained samples for routine fluorescence microscopy
G1508970	Glycerol PBS Mounting Medium	BioReagent,for microscopy,Suitable for Immunofluorescence(IF),for fluorescence analysis	Mounting material	Mounting after microfilament fluorescence staining	Suitable for maintaining sample hydration and observation stability after F-actin fluorescence staining
P1508975	Polyvinyl Alcohol Anti-Fluorescence Quenching Mounting Medium	Suitable for Immunofluorescence(IF),BioReagent,for microscopy,for fluorescence analysis	Anti-fade mounting medium	Mounting after fluorescent microfilament staining	Suitable for long-term preservation of fluorescent microfilament-stained sections or cell coverslips
P1508974	Polyvinyl Alcohol Glycerol Mounting Medium	BioReagent,for microscopy,Suitable for Immunofluorescence(IF),Suitable for Immunohistochemistry(IHC)	Mounting material	Mounting after microfilament fluorescence staining	Can be used for mounting after microfilament immunofluorescence or tissue-section fluorescence observation
A1508972	Gum Arabic Glycerol Mounting Medium	BioReagent,for microscopy,Suitable for microbiology,Suitable for Immunofluorescence(IF),Suitable for Immunohistochemistry(IHC)	Mounting material	Mounting after microfilament fluorescence staining	Can be used as a supporting mounting material for fluorescence/microscopic observation and is suitable for some immunostained samples

Microfilament staining should be selected according to the experimental question. For F-actin structural observation in fixed cells, fluorescent phalloidin or Actin-Tracker-type probes are preferred. For actin isoform analysis or myofibroblast marker detection, immunofluorescence is more appropriate. For dynamic rearrangement and cell migration processes, live-cell strategies such as LifeAct, Utrophin-ABD, F-tractin, or SiR-actin are suitable.

For more related articles, please see below:

[1] Microfilament staining and morphology observation experiment

[2] Cytoskeletal Staining Reagents