Active force maintains the stability of a contractile ring
Stanard Mebwe Pachong1, Kristian K Müller-Nedebock2,3
1Institute of Theoretical Physics, Department of Physics, Stellenbosch University, 7600, Stellenbosch, South Africa. stanard@aims-senegal.org.
The European Physical Journal. E, Soft Matter
|October 20, 2017
Summary
This study reveals how active and networking forces influence actin filament networks in contractile rings. The non-equilibrium active force is key to preventing ring breakdown and maintaining structural integrity.
Area of Science:
- Biophysics
- Cell Biology
- Soft Matter Physics
Background:
- Contractile rings, crucial for cell division, are complex networks of actin filaments and myosin motors.
- Understanding the structural dynamics of these networks under active forces is essential for cell biology.
Purpose of the Study:
- To investigate the structural integrity of polar actin filament networks cross-linked by myosin II within contractile rings.
- To determine the conditions under which active and networking forces lead to contractile ring breakdown.
Main Methods:
- Employing a functional integral formalism to model Langevin dynamics of rigid, cross-linked actin filaments.
- Utilizing the dynamical Random Phase Approximation (RPA) and one-dimensional Langevin dynamics simulation (LDS).
Main Results:
- Active and networking forces exhibit non-trivial diffusive behavior of filaments within the ring.
- Identified conditions leading to contractile ring breakdown due to these forces.
Conclusions:
- The non-equilibrium active force plays a predominant role in preventing gaps and maintaining the integrity of the contractile ring.
- This research provides insights into the mechanical stability of biological contractile structures.
Keywords:
Living systems: Biological networks
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