Actin Comet Tail
Actin Comet Tail - Related Videos
10:00
Assaying DNA Damage in Hippocampal Neurons Using the Comet Assay
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Cited by 21 •
2012
The comet assay is an efficient way of detecting single- and double-strand breaks, including alkali-labile sites and DNA-DNA/DNA-protein cross-links on the DNA in all cells including hippocampal neurons. The method takes advantage of the differential migration of DNA in an electric field due to differences in amount of DNA damage.
06:19
Comet Assay for DNA Damage Detection in Cells
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2025
The video demonstrates the comet assay for detecting DNA damage following exposure to harmful agents. Under alkaline conditions, the DNA unwinds and denatures, and upon electrophoresis, the undamaged and damaged DNA migrate differently in the agarose gel, forming a comet-shaped structure. The slowly migrating undamaged DNA forms the circular comet head, while the rapidly migrating damaged DNA fragments form the elongated comet tail.
08:23
Comet Assay as an Indirect Measure of Systemic Oxidative Stress
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Cited by 23 •
2015
Comet assay measures DNA breaks, induced by different factors. If all factors (except oxidative stress) causing DNA damage are kept constant, the amount of DNA damage is a good indirect parameter of oxidative stress. The goal of this protocol is to use comet assay for indirect measurement of oxidative stress.
07:53
Actin Co-Sedimentation Assay; for the Analysis of Protein Binding to F-Actin
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Cited by 18 •
2008
Proteins bind to filamentous actin (F-actin) through distinct actin binding modules. In this video we demonstrate the procedure of actin co-sedimentation, which is an in vitro assay routinely used to analyze proteins or specific domains that bind F-actin.
10:38
In Vivo Alkaline Comet Assay and Enzyme-modified Alkaline Comet Assay for Measuring DNA Strand Breaks and Oxidative DNA Damage in Rat Liver
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Cited by 17 •
2016
The alkaline comet assay measures DNA strand breaks in eukaryotic cells. By adding an Endonuclease III or human 8-oxoguanine-DNA-N-glycosylase digestion step, the assay can efficiently detect oxidative DNA damage. We describe methods for using these assays to detect DNA damage in rat liver.
FAQs
The Arp2/3 complex helps initiate host actin filament growth at the pathogen surface after pathogen-associated factors recruit the host machinery. Newly polymerized filaments push the pathogen forward, while older filaments disassemble behind it. This coordinated cycle converts localized actin assembly into directional movement through the host cytoplasm rather than simply producing a static filament structure.
Movement depends on balancing two linked processes: filament assembly at the particle’s surface and disassembly in the trailing region. Continuous growth supplies forward force, whereas removal of older filaments allows the tail to remodel as the particle advances. This dynamic organization distinguishes propulsion from an immobile actin coating and supports movement through the cytoplasm.
Pathogen-associated factors recruit host actin-nucleating machinery to the pathogen surface, redirecting a normally host-controlled cytoskeletal process toward microbial movement. The resulting actin assembly connects pathogen recognition or surface-associated signaling with mechanical propulsion. Studying this interaction helps identify how infectious agents manipulate host signaling pathways rather than merely resisting them.
Intracellular propulsion allows pathogens to remain within host cells while moving through the cytoplasm, reducing reliance on exposure outside the cell. Infections caused by Listeria and Shigella can use this strategy to move between cells. Cell-to-cell spread therefore links cytoskeletal manipulation with avoidance of extracellular immune defenses and continued infection.
For Listeria and Shigella, actin-based propulsion supports movement from one host cell to another. After entering or residing within a cell, pathogen-driven actin assembly can generate cytoplasmic movement that contributes to intracellular spread. This makes the comet tail relevant not only to cell biology, but also to understanding how infection progresses across neighboring host cells.
Analysis of these structures can reveal how pathogens recruit host actin-nucleating machinery, organize filament assembly, and couple cytoskeletal signaling to movement. In immunology and infection research, those findings clarify mechanisms of intracellular spread and host-pathogen interaction. They can also help identify stages of the propulsion process that may represent potential antimicrobial targets.