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Updated: May 12, 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
Coactosin accelerates cell dynamism by promoting actin polymerization.
Xubin Hou1, Tatsuya Katahira, Kazumasa Ohashi
1Department of Molecular Neurobiology, Graduate School of Life Sciences and Institute of Development, Aging & Cancer, Tohoku University, Japan.
Developmental Biology
|April 23, 2013
Summary
Coactosin, an actin-binding protein, is crucial for cell migration and neurite extension. It functions downstream of Rac signaling, actively participating in actin polymerization to drive these developmental processes.
Area of Science:
- Cell Biology
- Molecular Biology
- Developmental Biology
Background:
- Cellular development involves dynamic cell movement and process extension, driven by actin dynamics.
- Coactosin is an actin-binding protein identified in neural crest and neuroblastoma cells.
Purpose of the Study:
- To investigate the role of Coactosin in actin dynamics, cell migration, and neurite extension.
- To elucidate the relationship between Coactosin, Rac signaling, and actin polymerization.
Main Methods:
- Co-immunoprecipitation to assess protein associations.
- Overexpression and knockdown studies in cultured cells.
- Analysis of actin polymerization and cell migration.
- Rac signaling pathway manipulation using dominant-negative Rac1.
Main Results:
- Coactosin associates with actin and Capping protein, accumulating in cellular processes.
- Coactosin overexpression promotes cellular processes; knockdown disrupts actin polymerization and cell migration.
- Coactosin recruitment to lamellipodia/filopodia is Rac signaling-dependent.
- Functional Coactosin is required for Rac-mediated neural crest cell migration and neurite extension.
Conclusions:
- Coactosin acts downstream of Rac signaling to regulate actin polymerization.
- Coactosin plays a vital role in neurite extension and neural crest cell migration.
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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.
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.
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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.
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The high-order actin networks...
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