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

5.3K
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....
5.3K
Intracellular Signaling Affects Focal Adhesions01:17

Intracellular Signaling Affects Focal Adhesions

2.7K
Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...
2.7K
Integrins01:10

Integrins

4.0K
Animal and protozoan cells do not have cell walls to help maintain shape and provide structural stability. Instead, these eukaryotic cells secrete a sticky mass of carbohydrates and proteins into the spaces between adjacent cells. This network of proteins and molecules is called an extracellular matrix or ECM.
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
4.0K
The Role of Actin and Myosin in Non-muscle Cells01:10

The Role of Actin and Myosin in Non-muscle Cells

3.5K
Actin and myosin or actomyosin filaments also play a significant role in cells other than those involved in muscle contraction (which occurs within the sarcomere of muscle cells). The mechanism of non-muscle cell contractile bundles was first observed in Dictyostelium and Acanthamoeba. In non-muscle cells, two bundles are commonly found: stress fibers and actomyosin adherence belts. These contractile bundles are smaller and less organized than the ones found in muscle cells. They  are held...
3.5K
Activation of Integrins01:15

Activation of Integrins

3.5K
Integrins bind ligands and transmit information from outside the cell to inside or vice-versa through an "outside-in signaling" or "inside-out signaling."
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding...
3.5K
Introduction to Actin01:26

Introduction to Actin

5.2K
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...
5.2K

You might also read

Related Articles

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

Sort by
Same author

Neutralization of reactive oxygen species with cobinamide augments aortic dissections and rupture in BAPN-administered mice.

American journal of physiology. Heart and circulatory physiology·2026
Same author

Rare type I collagen variants in early-onset bicuspid aortic valve disease: Overlap with Ehlers-Danlos syndrome and osteogenesis imperfecta.

HGG advances·2026
Same author

The aorta in Marfan syndrome - from molecular mechanisms to mechanobiological dysfunction.

Cardiovascular research·2026
Same author

Moyamoya syndrome in a patient with pathogenic heterozygous variant in the <i>SETD5</i> gene: A case report.

Brain circulation·2026
Same author

Using bioinformatic tools to identify high-risk variants of uncertain significance in aortopathy genes that increase aortic dissection risk.

Genetics in medicine : official journal of the American College of Medical Genetics·2026
Same author

Epigenetic Programming of Macrophage Phenotypes by STING-IRF3 Drives Inflammation in Ascending Thoracic Aortic Dissection.

bioRxiv : the preprint server for biology·2026

Related Experiment Video

Updated: Jul 27, 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

8.0K

Smooth Muscle-Alpha Actin R149C Pathogenic Variant Downregulates Integrin Recruitment at Cell-Matrix Adhesions and

Krishna R Ojha1, Hyoseon Kim2, Samuel Padgham1

  • 1Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX 77807, USA.

International Journal of Molecular Sciences
|June 10, 2023
PubMed
Summary

Pathogenic variants in ACTA2 impair aortic smooth muscle cell contraction, leading to thoracic aortic aneurysms. This study reveals altered actin isoform expression and reduced integrin recruitment in mutant cells, decreasing aortic contractility.

Keywords:
Acta2R149C/+ miceactinintegrinsvascular smooth muscle cells

More Related Videos

Isolation of Primary Patient-specific Aortic Smooth Muscle Cells and Semiquantitative Real-time Contraction Measurements In Vitro
08:28

Isolation of Primary Patient-specific Aortic Smooth Muscle Cells and Semiquantitative Real-time Contraction Measurements In Vitro

Published on: February 15, 2022

3.8K
Probing Myosin Ensemble Mechanics in Actin Filament Bundles Using Optical Tweezers
06:53

Probing Myosin Ensemble Mechanics in Actin Filament Bundles Using Optical Tweezers

Published on: May 4, 2022

2.3K

Related Experiment Videos

Last Updated: Jul 27, 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

8.0K
Isolation of Primary Patient-specific Aortic Smooth Muscle Cells and Semiquantitative Real-time Contraction Measurements In Vitro
08:28

Isolation of Primary Patient-specific Aortic Smooth Muscle Cells and Semiquantitative Real-time Contraction Measurements In Vitro

Published on: February 15, 2022

3.8K
Probing Myosin Ensemble Mechanics in Actin Filament Bundles Using Optical Tweezers
06:53

Probing Myosin Ensemble Mechanics in Actin Filament Bundles Using Optical Tweezers

Published on: May 4, 2022

2.3K

Area of Science:

  • Cardiovascular Biology
  • Cellular and Molecular Medicine
  • Genetics and Genomics

Background:

  • Thoracic aortic aneurysms (TAAs) are associated with pathogenic variants in the ACTA2 gene.
  • ACTA2 missense variants are linked to impaired smooth muscle cell (SMC) contractility within the aorta.

Purpose of the Study:

  • To investigate how ACTA2 variants affect actin isoform expression and integrin recruitment.
  • To determine the impact of these molecular changes on aortic smooth muscle cell contractility and potential contribution to TAAs.

Main Methods:

  • Analysis of thoracic aortic rings from Acta2 variant mice using stress relaxation measurements.
  • Assessment of contractile responses to phenylephrine and potassium chloride.
  • Immunofluorescence microscopy to quantify actin isoform expression (SMα-actin, SMγ-actin) and integrin recruitment (α5β1, α2β1) in SMCs.

Main Results:

  • Aorta from Acta2 variant mice showed reduced stress relaxation at low tension.
  • Contractile responses were significantly lower (50%) in Acta2 variant mice compared to wild-type.
  • Mutant SMCs exhibited decreased SMα-actin and increased SMγ-actin, alongside reduced α5β1 and α2β1 integrin recruitment.

Conclusions:

  • Downregulation of SMα-actin and upregulation of SMγ-actin in Acta2 variant SMCs contribute to reduced contractility and potentially increased stiffness.
  • Impaired integrin recruitment further compromises SMC-matrix interactions.
  • These cellular dysfunctions are implicated as long-term contributors to the development of thoracic aortic aneurysms.