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The Mechanics of Poro-Elastic Contractile Actomyosin Networks As a Model System of the Cell Cytoskeleton
Published on: March 10, 2023
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ER-PM Contacts Define Actomyosin Kinetics for Proper Contractile Ring Assembly.
Dan Zhang1, Tamara C Bidone2, Dimitrios Vavylonis2
1Temasek Life Sciences Laboratory, 1 Research Link, Singapore 117604, Singapore.
Current Biology : CB
|February 16, 2016
Summary
Endoplasmic reticulum-plasma membrane contacts regulate actomyosin ring assembly in fission yeast. These contacts control actin cable distribution and compaction kinetics, ensuring robust ring formation.
Area of Science:
- Cell biology
- Biophysics
- Molecular and Cellular Physiology
Background:
- The cortical endoplasmic reticulum (ER) forms contact sites with the plasma membrane (PM) via specific protein tethers.
- The precise physiological roles of these ER-plasma membrane contacts are not fully elucidated.
Purpose of the Study:
- To investigate the function of ER-plasma membrane contacts in actomyosin ring assembly in Schizosaccharomyces pombe.
- To understand how these contacts influence the kinetics and distribution of ring components during assembly.
Main Methods:
- Quantitative image analysis of fission yeast cells.
- Computer simulations of ring component dynamics.
- Genetic manipulation to disrupt ER-PM contacts.
Main Results:
- Fission yeast cells lacking ER-PM contacts show abnormal actin cable clustering during actomyosin ring assembly.
- These cells are sensitive to impaired actin filament crosslinking.
- ER-PM contacts modulate the distribution of ring components and restrict their compaction rate.
Conclusions:
- ER-plasma membrane contacts act as crucial physical modulators for robust actomyosin ring assembly.
- These contacts play a kinetic restriction role in the ring compaction process.
- The findings reveal a novel function for ER-PM contacts in cytoskeletal dynamics.
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