Related Experiment Video
Updated: Jun 9, 2026
06:54
A Time-Efficient Fluorescence Spectroscopy-Based Assay for Evaluating Actin Polymerization Status in Rodent and Human Brain Tissues
Published on: June 3, 2021
Myosin IIb regulates actin dynamics during synaptic plasticity and memory formation.
Christopher S Rex1, Cristin F Gavin, Maria D Rubio
1Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697, USA.
Neuron
|August 28, 2010
Summary
Myosin II motor activity drives actin reorganization essential for synaptic plasticity and memory consolidation. This research reveals a mechanical framework for understanding how cytoskeletal forces stabilize memory formation.
Area of Science:
- Neuroscience
- Cell Biology
- Biophysics
Background:
- Actin cytoskeleton reorganization is crucial for synaptic plasticity and memory.
- Mechanisms controlling actin dynamics in these processes remain unclear.
Purpose of the Study:
- Investigate the role of myosin II motor activity in synaptic plasticity and memory formation.
- Elucidate the mechanical forces governing actin cytoskeleton dynamics during memory processes.
Main Methods:
- Utilized pharmacological inhibitors and promoters of actin polymerization.
- Assessed the impact of myosin II inhibition on long-term potentiation (LTP) and memory consolidation.
- Analyzed the formation of actin structures in response to synaptic stimulation.
Main Results:
- Myosin II activity is downstream of LTP induction and required for specialized actin structures.
- Myosin II contributes to actin-dependent memory consolidation.
- Promoting actin polymerization counteracted the effects of myosin II inhibition on LTP and memory.
Conclusions:
- Myosin II motors impart mechanical forces on the actin cytoskeleton, regulating synaptic plasticity.
- These forces trigger actin structure emergence, stabilizing synaptic plasticity and memory.
- A mechanical framework is proposed for cytoskeletal dynamics in synaptic plasticity and memory.
Related Concept Videos
01:15Overview of Myosin Structure and Function
Myosins are a family of molecular motor proteins, first identified in the skeletal muscles, where they are responsible for muscle contraction. Along with their role in muscle contraction, these proteins also play a role in the intracellular transport of molecules and vesicles. There are twenty-four classes of myosins based on their domain sequence and organization. Of the twenty-four, six classes (Myosin I, Myosin II, Myosin V, Myosin VI, Myosin VII, and Myosin X) have been well characterized.
01:29Relaxation of Skeletal Muscles
The period of muscle contraction primarily influences the duration of stimulation at the neuromuscular junction (NMJ), the presence of free calcium ions in the sarcoplasm, and the availability of energy or ATP to support contractions.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.
01:18Role of Myosin in Cell Migration
Myosins are multimeric motor proteins involved in various cellular processes such as migration, adhesion, and proliferation. Myosin II is the most common type in animal cells, which binds and cross-links actin filaments.
Myosin II is a hexamer comprising two heavy chains with globular heads and coiled-coil tails, two regulatory light chains, and two essential light chains. The ATPase sites on the myosin heads hydrolyze ATP, and the released phosphate generates the force for contraction. It is...
Myosin II is a hexamer comprising two heavy chains with globular heads and coiled-coil tails, two regulatory light chains, and two essential light chains. The ATPase sites on the myosin heads hydrolyze ATP, and the released phosphate generates the force for contraction. It is...
01:16Actin 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...
01:08The Sarcomere
A sarcomere is a microscopic segment repeating in a myofibril. The sarcomere fundamentally consists of two main myofilaments: thick filaments called myosin and thin filaments called actin. These filaments interact by sliding past each other in response to stimulus. In addition to myosin and actin, several other proteins, such as tropomyosin, troponin, titin, nebulin, myomesin, α-actinin, and dystrophin, play crucial roles in regulating, structuring, and functioning of the sarcomere.
Each myosin...
Each myosin...
01:26Cross-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.