Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Actin Polymerization and Cell Motility01:13

Actin Polymerization and Cell Motility

7.3K
Actin is a family of globular proteins that are highly abundant in eukaryotic cells. It makes up approximately 1-5% of total cell protein concentration. Actin monomers polymerize to form a complex network of polarized filaments, the actin cytoskeleton, that plays a crucial role in many cellular processes, including cell motility, division, endocytosis, and metastasis of cancer cells.
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate....
7.3K
The Movement of Organelles and Vesicles01:43

The Movement of Organelles and Vesicles

7.5K
In eukaryotic cells,  cytoskeletal filaments such as actin, microtubules, and intermediate filaments form a mesh-like cytoskeletal network. These filaments serve as tracks for transporting cellular cargo. Specialized motor proteins use the chemical energy stored in adenosine triphosphate (ATP) for this transport. During interphase, microtubules are polarized, with the plus-end towards the cell periphery and the minus-end towards the cell center. Two microtubule-associated motor proteins,...
7.5K
Actin Polymerization01:42

Actin Polymerization

9.2K
Actin polymerization occurs through the head-to-tail association of binding sites on monomeric actin or G-actin to form filamentous or F-actin. The polymerization can be divided into three phases ̶  nucleation, elongation, and steady-state phase.
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight...
9.2K
Actin Treadmilling01:18

Actin Treadmilling

10.3K
Actin filaments undergo polymerization and depolymerization from either end. The polymerization and depolymerization rates depend on the cytosolic concentration of free G-actins. The polymerization rate is generally higher at the plus or barbed end, while the depolymerization rate is higher at the minus or pointed end. At a steady state, critical concentration describes the concentration of free G-actin monomers at which the polymerization rate at the plus end is equal to that of the...
10.3K
Introduction to Actin01:26

Introduction to Actin

7.1K
Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle cells, while in non-muscle cells, it is lower and makes up around 1–5 percent of the total cell protein. Actin found in the unicellular amoebae and complex multicellular animals is around 80% similar, demonstrating their conservation over a billion years of evolution.  Actin coding genes are conserved within species and across...
7.1K
Intracellular Movement of Viruses and Bacteria01:10

Intracellular Movement of Viruses and Bacteria

3.9K
Intracellular bacteria and viruses often comprise a group of highly infectious pathogens that can cause several diseases. Bacterial pathogens include those belonging to the genus Rickettsia responsible for conditions such as rocky mountain spotted fever and the Mediterranean spotted fever; Chlamydia, a genus responsible for a sexually transmitted disease; Coxiella burnetii, an agent responsible for Q fever. Viral pathogens include vaccinia—a poxvirus, and herpes simplex virus—a...
3.9K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The Opposite Effects of ROCK and Src Kinase Inhibitors on Susceptibility of Eukaryotic Cells to Invasion by Bacteria Serratia grimesii.

Biochemistry. Biokhimiia·2019
Same author

[ENTRY OF FACULTATIVE PATHOGEN SERRATIA GRIMESII INTO HELA CELLS. ELECTRON MICROSCOPIC ANALYSIS].

Tsitologiia·2016
Same author

Heat shock protein DnaK--substrate of actin-specific bacterial protease ECP32.

Biochemistry. Biokhimiia·2011
Same author

Probing for actinase activity of protealysin.

Biochemistry. Biokhimiia·2009
Same author

Decreased sensitivity of transformed 3T3-SV40 cells treated with N-acetylcysteine to bacterial invasion.

Bulletin of experimental biology and medicine·2007
Same author

Invasive characteristics of apathogenic Shigella flexneri 5a2c mutant obtained under the effect of furazolidone.

Bulletin of experimental biology and medicine·2004
Same journal

Multidirectional Effects of SARS-CoV-2 Coronavirus Proteins on Amyloid Transformation of Alpha-Synuclein.

Biochemistry. Biokhimiia·2026
Same journal

Dependence of Antioxidant and Transcriptional Responses to Periodic Hypoxia on Sex and Age in Rats.

Biochemistry. Biokhimiia·2026
Same journal

Effect of the PPARγ Agonist Pioglitazone on Rat Behavior and Expression of Epileptogenesis-Related Genes during the Latent Phase of the Lithium-Pilocarpine Model.

Biochemistry. Biokhimiia·2026
Same journal

A Conjugate of Aminoadamantane and Tetrahydro-γ-Carboline Inhibits Accumulation of Mutant α-Synuclein A53T in the Cellular Model of Proteinopathy.

Biochemistry. Biokhimiia·2026
Same journal

Immunoinflammatory Markers in Patients with Affective Disorders: Genetic Polymorphisms, Peripheral Cytokine Levels, and Expression of IL-1β, IL-13, TNF-β, and TGF-α in Peripheral Blood Mononuclear Cells.

Biochemistry. Biokhimiia·2026
Same journal

Method for Individual Assessment of Human Cerebral Cortex Activity by a Combined Use of Magnetic Resonance Spectroscopy of Glutamate and BOLD Signal Method.

Biochemistry. Biokhimiia·2026
See all related articles

Related Experiment Video

Updated: Apr 21, 2026

In Vitro Polymerization of F-actin on Early Endosomes
12:15

In Vitro Polymerization of F-actin on Early Endosomes

Published on: August 28, 2017

9.7K

Intracellular transport based on actin polymerization.

S Yu Khaitlina1

  • 1Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russia. skhspb@gmail.com.

Biochemistry. Biokhimiia
|November 12, 2014
PubMed
Summary
This summary is machine-generated.

The cell uses two actin-based transport systems: actomyosin, driven by myosin, and a unique polymerization system. This polymerization system, crucial for moving particles like vesicles and bacteria, relies on actin polymerization and specific proteins.

More Related Videos

Reconstitution of Actin-Based Motility with Commercially Available Proteins
08:40

Reconstitution of Actin-Based Motility with Commercially Available Proteins

Published on: October 28, 2022

2.4K
Visualizing Actin and Microtubule Coupling Dynamics In Vitro by Total Internal Reflection Fluorescence TIRF Microscopy
08:44

Visualizing Actin and Microtubule Coupling Dynamics In Vitro by Total Internal Reflection Fluorescence TIRF Microscopy

Published on: July 20, 2022

4.2K

Related Experiment Videos

Last Updated: Apr 21, 2026

In Vitro Polymerization of F-actin on Early Endosomes
12:15

In Vitro Polymerization of F-actin on Early Endosomes

Published on: August 28, 2017

9.7K
Reconstitution of Actin-Based Motility with Commercially Available Proteins
08:40

Reconstitution of Actin-Based Motility with Commercially Available Proteins

Published on: October 28, 2022

2.4K
Visualizing Actin and Microtubule Coupling Dynamics In Vitro by Total Internal Reflection Fluorescence TIRF Microscopy
08:44

Visualizing Actin and Microtubule Coupling Dynamics In Vitro by Total Internal Reflection Fluorescence TIRF Microscopy

Published on: July 20, 2022

4.2K

Area of Science:

  • Cell Biology
  • Biochemistry
  • Molecular Biology

Background:

  • Intracellular transport relies on microtubule-based systems and two distinct actin-based systems.
  • Actin-based transport involves either myosin motor proteins or unidirectional actin polymerization.
  • The actin polymerization system utilizes proteins like WASP/Scar and Arp2/3, forming 'comet-like tails' for cargo movement.

Purpose of the Study:

  • To review current understanding of actin polymerization and its regulation.
  • To elucidate the mechanisms of intracellular actin-based vesicular transport.
  • To highlight the role of actin-binding proteins in cellular transport.

Main Methods:

  • Review of existing literature on intracellular transport mechanisms.
  • Analysis of high-performance electron microscopy and electron tomography data.
  • Examination of cell-free systems, including Xenopus oocyte extracts.

Main Results:

  • Two actin-based transport systems exist: actomyosin (myosin-driven) and non-myosin (actin polymerization-driven).
  • Actin polymerization forms 'comet-like tails' responsible for moving bacteria, vesicles, and phagosomes.
  • This mechanism is essential for various cellular processes, including membrane raft transport and nuclear spindle positioning.

Conclusions:

  • Actin polymerization is a key driver of intracellular transport, independent of motor proteins.
  • Proteins of the WASP/Scar family and Arp2/3 complex are critical for actin-based transport.
  • Understanding these actin-based systems provides insights into fundamental cellular mechanics and disease processes.