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Updated: Sep 4, 2025
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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
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Universal catastrophe time distributions of dynamically unstable polymers.
Paul B Dieterle1, Jenny Zheng2, Ethan Garner2
1Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Physical Review. E
|July 20, 2022
Summary
Dynamic instability in biopolymers, involving growth and shrinkage, is explained by polymerization and hydrolysis. Our study reveals that monomer depletion from finite pools significantly alters catastrophe time distributions, impacting filament dynamics.
Area of Science:
- Biophysics
- Polymer Dynamics
- Cell Biology
Background:
- Dynamic instability, characterized by growth, catastrophe, and shrinkage, is a fundamental property of quasi-one-dimensional biopolymers.
- Existing models attribute catastrophic cessation of growth and depolymerization to the interplay of hydrolysis and polymerization at the filament tip.
Purpose of the Study:
- To investigate the catastrophe time distribution in biopolymer dynamic instability.
- To determine the influence of monomer availability and noise on this distribution.
Main Methods:
- Theoretical modeling of biopolymer dynamics.
- Analysis of catastrophe models under varying monomer pool conditions.
- Derivation of catastrophe time distributions.
Main Results:
- For many catastrophe models, the expected catastrophe time distribution is exponential.
- Distribution shape is largely insensitive to noise.
- Depletion of monomers from a finite pool significantly alters the distribution by reducing polymerization rates, even when polymerization rates are only slightly affected.
Conclusions:
- Finite monomer pool effects are crucial for understanding biopolymer dynamic instability.
- The derived finite-pool catastrophe time distribution provides a more accurate model for filament dynamics in cellular environments.
- These findings have implications for understanding cytoskeletal dynamics and related cellular processes.
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