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Updated: Aug 4, 2026
12:15
In Vitro Polymerization of F-actin on Early Endosomes
Published on: August 28, 2017
Low concentration of reserpine accelerates actin polymerization via interaction with G-actin
S Nakamura1, K Ohmi, Y Nonomura
1Department of Pharmacology, Faculty of Medicine, University of Tokyo, Japan.
Molecular Pharmacology
|June 1, 1988
Summary
Reserpine accelerates actin polymerization at low concentrations by binding to G-actin, not F-actin. This interaction influences the dynamics of actin assembly, impacting cellular processes.
Area of Science:
- Biochemistry
- Cell Biology
Background:
- Actin polymerization is crucial for cellular functions.
- Understanding the regulation of actin dynamics is essential for cell biology research.
Purpose of the Study:
- To investigate the effect of reserpine on actin polymerization.
- To determine the binding interaction of reserpine with actin monomers (G-actin) and polymers (F-actin).
Main Methods:
- Measurement of high shear viscosity to assess polymerization.
- Electron microscopy for visualizing actin structures.
- Sephadex G-50 gel filtration and photoaffinity labeling to study reserpine-actin binding.
Main Results:
- Low concentrations of reserpine (up to ~0.5 nM) accelerated actin polymerization in a dose-dependent manner.
- Reserpine preferentially bound to G-actin, with minimal binding to F-actin.
- Photoaffinity labeling confirmed covalent binding of reserpine to G-actin.
Conclusions:
- Reserpine influences actin polymerization dynamics.
- The observed effects are mediated through reserpine's interaction with G-actin.
Related Concept Videos
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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 actin...
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 actin...
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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...
Arp2/3 Complex
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01:19Actin Filament Depolymerization
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In F-actin, the ADF/cofilin proteins...
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Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.
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01:18Actin Treadmilling
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