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

Generation of Straight or Branched Actin Filaments01:14

Generation of Straight or Branched Actin Filaments

3.0K
The straight or branched structure formation of actin filaments is controlled by nucleating proteins such as the formins and Arp2/3 complex. Formin-mediated assembly results in straight filaments, whereas Arp2/3 protein complex-mediated assembly results in branched actin filaments.
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
3.0K
Actin Filament Depolymerization01:19

Actin Filament Depolymerization

3.2K
Actin filaments (F-actin) are composed of actin subunits. The dissociation of actin monomers can occur from either end of F-actin. The rate of dissociation is faster from the minus-end or the pointed end, where the actin subunits exist with a bound ADP, together known as ADP-actin. The depolymerization of F-actin is aided by proteins, including the actin-depolymerizing factor (ADF) and cofilin family of proteins, gelsolin, and glia maturation factor (GMF).
In F-actin, the ADF/cofilin proteins...
3.2K
Actin Polymerization01:42

Actin Polymerization

6.9K
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...
6.9K
Actin Treadmilling01:18

Actin Treadmilling

8.2K
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...
8.2K
Actin Polymerization and Cell Motility01:13

Actin Polymerization and Cell Motility

5.4K
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....
5.4K
Introduction to Actin01:26

Introduction to Actin

5.3K
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...
5.3K

You might also read

Related Articles

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

Sort by
Same author

Fecal Microbiota Transplantation Is Associated with Better Survival Compared to Standard of Care in Severe Alcoholic Hepatitis Not Responding to Corticosteroids: A Systematic Review and Meta-Analysis.

Journal of clinical medicine·2026
Same author

Large-Scale Structural Dynamics in the Tail Fiber Modulate the Infective Transition of the T7 Bacteriophage.

Small (Weinheim an der Bergstrasse, Germany)·2026
Same author

High-Intensity Training Increases Osteocalcin Levels: A Meta-Analysis of Effects of Exercise on Bone Remodeling biomarkers.

Sports medicine - open·2026
Same author

Podocin oligomers regulate the ordering of nephrin chains, providing the molecular basis of <i>NPHS2</i> interallelic interactions.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

Sorbitol modulates the structure and nanomechanics of κ-casein amyloid fibrils.

Biophysical journal·2026
Same author

Plastic versus metallic stents for endoscopic ultrasound-guided hepaticogastrostomy in malignant biliary obstruction: a systematic review and meta-analysis.

Therapeutic advances in gastroenterology·2026

Related Experiment Video

Updated: Sep 13, 2025

Aip1p Dynamics Are Altered by the R256H Mutation in Actin
08:57

Aip1p Dynamics Are Altered by the R256H Mutation in Actin

Published on: July 30, 2014

8.1K

Titin's Intrinsically Disordered PEVK Domain Modulates Actin Polymerization.

Áron Gellért Altorjay1, Hedvig Tordai1, Ádám Zolcsák1

  • 1Department of Biophysics and Radiaton Biology, Semmelweis University, 1085 Budapest, Hungary.

International Journal of Molecular Sciences
|July 29, 2025
PubMed
Summary

Titin

Keywords:
AlphaFoldPEVKactin paracrystalatomic force microscopyintrinsically unstructured protein domainpolymerization assaypyrene actinsupported lipid bilayertitin

More Related Videos

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

3.6K
Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles
08:02

Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles

Published on: May 5, 2022

2.7K

Related Experiment Videos

Last Updated: Sep 13, 2025

Aip1p Dynamics Are Altered by the R256H Mutation in Actin
08:57

Aip1p Dynamics Are Altered by the R256H Mutation in Actin

Published on: July 30, 2014

8.1K
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

3.6K
Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles
08:02

Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles

Published on: May 5, 2022

2.7K

Area of Science:

  • Muscle protein structure and function
  • Biochemistry and molecular biology
  • Cytoskeletal dynamics

Background:

  • Titin is a multi-domain muscle protein crucial for sarcomere elasticity and mechanosensing.
  • The titin PEVK domain, rich in proline and charged residues, is intrinsically disordered.
  • Previous studies indicated PEVK domain binds F-actin, but its effect on actin assembly was unknown.

Purpose of the Study:

  • To investigate the impact of the titin PEVK domain on actin assembly dynamics.
  • To characterize the structural effects of PEVK on F-actin.
  • To explore the potential role of PEVK in regulating sarcomeric actin.

Main Methods:

  • Cloning, expression, and purification of the PEVKII segment of titin's PEVK domain.
  • Monitoring actin assembly kinetics using the pyrene assay.
  • Structural analysis of F-actin-PEVKII complexes via atomic force microscopy (AFM).

Main Results:

  • PEVKII significantly enhanced actin assembly rates and peak F-actin quantity in a concentration-dependent manner.
  • PEVKII did not alter the critical concentration for actin polymerization, suggesting nucleation facilitation.
  • AFM revealed radially symmetric complexes of short actin filaments in the presence of PEVKII.

Conclusions:

  • The titin PEVK domain acts as an actin polymerization accelerator by promoting nucleation.
  • This PEVK-mediated modulation of actin assembly may regulate sarcomeric actin length and turnover.
  • Titin's PEVK domain functions not only in sarcomeric shortening but also in modulating actin polymerization.