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

Motor Unit Stimulation01:20

Motor Unit Stimulation

When the neuron of a motor unit fires an action potential, it triggers a series of events, leading to a twitch contraction in the muscle fibers. The process of excitation-contraction coupling is crucial in relaying the action potential to the muscle fibers.
The latent period of contraction marks the onset of excitation-contraction coupling, when the action potential propagates across the sarcolemma, preparing the muscle fibers for contraction. As the fibers enter the contraction phase, the...
Actin and Myosin in Muscle Contraction01:16

Actin and Myosin in Muscle Contraction

Actin and myosin are contractile proteins that form the sarcomere found in skeletal muscle tissues for regulating muscle contraction. Actin, a globular contractile protein, interacts with myosin for muscle contraction. The skeletal tissue appears striped or striated under a microscope due to the repeated arrangement of contractile proteins actin and myosin along the length of myofibrils. Dark A bands and light I bands repeat along myofibrils, and the alignment of myofibrils in the cell causes...
Excitation-Contraction Coupling in Skeletal Muscles01:20

Excitation-Contraction Coupling in Skeletal Muscles

Excitation-contraction coupling is a series of events that occur between generating an action potential and initiating a muscle contraction. It occurs at the triad, a structure found in skeletal muscle fibers that comprise a T-tubule and terminal cisternae of the sarcoplasmic reticulum on each side. These triads are visible in longitudinally sectioned muscle fibers. They are typically located at the A-I junction — the junction between the A and I bands of the sarcomere.
When an action potential...
Muscle Contraction01:10

Muscle Contraction

In skeletal muscles, acetylcholine is released by nerve terminals at the motor endplate—the point of synaptic communication between motor neurons and muscle fibers. The binding of acetylcholine to its receptors on the sarcolemma allows entry of sodium ions into the cell and triggers an action potential in the muscle cell. Thus, electrical signals from the brain are transmitted to the muscle. Subsequently, the enzyme acetylcholinesterase breaks down acetylcholine to prevent excessive muscle...
Muscle Contraction01:15

Muscle Contraction

Cross-bridge Cycle01:26

Cross-bridge Cycle

As muscle contracts, the overlap between the thin and thick filaments increases, decreasing the length of the sarcomere—the contractile unit of the muscle—using energy in the form of ATP. At the molecular level, this is a cyclic, multistep process that involves binding and hydrolysis of ATP, and movement of actin by myosin.

You might also read

Related Articles

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

Sort by
Same author

Optimizing electro-responsive glyoxal-crosslinked alginate hydrogel for the electrochemical detection of NADH and antibacterial activity in smart dressing biointerfaces.

International journal of biological macromolecules·2026
Same author

Proximal junctional kyphosis and failure risk around the thoracolumbar junction: Impact of anterior malalignment, pelvic retroversion, and upper instrumented level selection.

Brain & spine·2026
Same author

Corrigendum: Biomimetic engineering of conductive curli protein films (2018<i>Nanotechnology</i>29 454002).

Nanotechnology·2026
Same author

Three-Dimensional Magnetoelectric Nanocomposite GelMA Hydrogels for Wireless Electrical Stimulation of Cardiac Cells.

ACS applied materials & interfaces·2026
Same author

Idiopathic Thoracolumbar Scoliosis Treated at Adult Age: Timing of Surgery and Quality of Life.

Spine·2026
Same author

Biological evaluation of amidine derivatives: In vitro cytotoxicity and cellular antioxidant capacity.

PloS one·2026

Related Experiment Video

Updated: Jul 17, 2026

Fabrication of Carbon-Based Ionic Electromechanically Active Soft Actuators
14:42

Fabrication of Carbon-Based Ionic Electromechanically Active Soft Actuators

Published on: April 25, 2020

Contraction process of an electroactive actuator based on a one microsecond atomistic molecular dynamics simulation.

David Zanuy1, Carlos Alemán

  • 1Departament d'Enginyeria Química, E.T.S. d'Enginyeria Industrial de Barcelona, Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028, Spain. david.zanuy@upc.edu

Chemistry (Weinheim an Der Bergstrasse, Germany)
|January 4, 2007
PubMed
Summary

Molecular dynamics simulations reveal electroactive actuator contraction occurs non-concertedly. Calixarene conformational changes and solvent molecules significantly influence actuator efficiency and contraction rate.

More Related Videos

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops
06:48

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops

Published on: July 11, 2025

Fabrication Process of Silicone-based Dielectric Elastomer Actuators
10:32

Fabrication Process of Silicone-based Dielectric Elastomer Actuators

Published on: February 1, 2016

Related Experiment Videos

Last Updated: Jul 17, 2026

Fabrication of Carbon-Based Ionic Electromechanically Active Soft Actuators
14:42

Fabrication of Carbon-Based Ionic Electromechanically Active Soft Actuators

Published on: April 25, 2020

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops
06:48

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops

Published on: July 11, 2025

Fabrication Process of Silicone-based Dielectric Elastomer Actuators
10:32

Fabrication Process of Silicone-based Dielectric Elastomer Actuators

Published on: February 1, 2016

Area of Science:

  • Materials Science
  • Computational Chemistry
  • Polymer Science

Background:

  • Electroactive actuators offer potential for molecular machines and soft robotics.
  • Understanding the microscopic mechanisms of actuation is crucial for designing efficient devices.
  • Calixarene and quaterthiophene-based systems are promising candidates for electroactive materials.

Purpose of the Study:

  • To investigate the microscopic contraction mechanism of a calix[4]arene-quaterthiophene electroactive actuator.
  • To elucidate the role of conformational transitions and solvent effects on actuator performance.
  • To provide insights into the design principles for enhanced electroactive actuator materials.

Main Methods:

  • Atomistic molecular dynamics (MD) simulations were employed.
  • Simulations were conducted in dichloromethane solution with explicit solvent molecules.
  • A 1-microsecond trajectory of the oxidized and deprotonated actuator was analyzed.

Main Results:

  • The actuator contraction proceeds via a non-concerted mechanism, with individual units acting independently.
  • Secondary conformational transitions in calix[4]arene scaffolds, specifically phenolate ring rotational isomerism, can limit molecular length reduction.
  • Despite potential limitations in length change, actuator power is maintained due to compact arrangement capabilities.
  • Solvent molecules were found to significantly reduce the contraction rate by approximately three orders of magnitude.

Conclusions:

  • The contraction mechanism is complex, influenced by both intramolecular conformational dynamics and intermolecular solvent interactions.
  • Calixarene conformational flexibility presents a trade-off between length change efficiency and maintaining actuation power.
  • Solvent effects play a critical role in modulating the kinetics of the electroactive actuator's response.
  • Further research should focus on mitigating negative conformational effects and optimizing solvent environments for improved actuator performance.