Translocation of a Polymer through a Crowded Channel under Electrical Force

Area of Science:

• Polymer physics
• Biophysics
• Computational modeling

Background:

• Understanding polymer chain dynamics is crucial for biological processes.
• Crowded environments significantly alter polymer behavior.
• Cylindrical channel translocation is relevant to molecular transport in cells.

Purpose of the Study:

• To investigate polymer chain translocation through a crowded cylindrical channel.
• To evaluate the impact of field strength, chain length, and crowding on translocation dynamics.
• To provide insights applicable to protein translocation.

Main Methods:

• Langevin dynamics simulations were employed.
• System parameters included field strength (F), chain length (N), and crowding extent (ρ).
• Analysis focused on translocation time, probability, shape factor, and segment distribution.

Main Results:

• A scaling relation τ ~ F^-α was observed, with α increasing with crowding.
• Translocation probability showed inverse dependence on field strength in crowded vs. uncrowded channels.
• Translocation time exhibited exponential growth with crowding extent.
• Shape factor and internal segment number displayed distinct behaviors during translocation.

Conclusions:

• Crowding significantly modifies polymer translocation dynamics.
• The findings offer valuable information for understanding and potentially manipulating protein translocation.
• Simulation results highlight the complex interplay between confinement, crowding, and external forces.