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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
Encounter dynamics of a small target by a polymer diffusing in a confined domain
A Amitai1, C Amoruso, A Ziskind
1Ecole Normale Supérieure, Institute of Biology (IBENS), Group of Computational Biology and Applied Mathematics, 46 rue d'Ulm, 75005 Paris, France.
The Journal of Chemical Physics
|January 3, 2013
Summary
We investigated polymer dynamics, finding the narrow encounter time (NETP) to a target varies with polymer length. The NETP shows complex behavior, including an exponential scaling law in certain regimes.
Area of Science:
- Polymer Physics
- Biophysics
- Computational Biology
Background:
- Understanding polymer dynamics is crucial for biological processes.
- Polymers interact with targets in cellular environments, influencing function.
- First passage time is a key metric for molecular interactions.
Purpose of the Study:
- To investigate the narrow encounter time (NETP) for a polymer to reach a surface microdomain target.
- To analyze how polymer length and monomer absorption rules affect NETP.
- To provide a model applicable to DNA-protein and mRNA-target interactions.
Main Methods:
- Freely joint chain polymer model.
- Brownian dynamics simulations.
- Analysis of two absorption scenarios: any monomer or a single specific monomer.
Main Results:
- NETP initially increases with polymer length, then decreases, exhibiting an exponential scaling law for long polymers.
- When only one monomer can be absorbed, its position significantly impacts NETP.
- Identified distinct behaviors based on absorption conditions.
Conclusions:
- Polymer length and absorption mechanism critically influence target encounter time.
- The NETP model offers insights into DNA-target binding in chromatin and mRNA interactions.
- Simulation results provide a foundation for further theoretical and experimental studies.
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