Hydrodynamic coupling for particle-based solvent-free membrane models.

Area of Science:

• Biophysics
• Computational Biology
• Materials Science

Background:

• Biological membranes involve diverse scales, from nanometers/picoseconds to micrometers/milliseconds.
• Current solvent-free coarse-grained models offer convenience but often lack realistic kinetics.
• Introducing hydrodynamic coupling in these models is computationally expensive and challenging.

Purpose of the Study:

• To introduce a computationally efficient framework for modeling hydrodynamic coupling in coarse-grained membrane simulations.
• To improve the accuracy of kinetic descriptions in large-scale membrane dynamics.
• To provide insights into slow cellular signaling processes involving membranes.

Main Methods:

• Anisotropic Langevin dynamics framework.
• Modeling hydrodynamic effects using friction and diffusion tensors derived from Stokes equations.
• Integration with a recently developed coarse-grained membrane model.
• Analysis of dispersion relations for planar membrane patches.

Main Results:

• Accurate dispersion relations for free-standing and wall-confined membrane patches were obtained.
• The framework successfully models in-plane and out-of-plane hydrodynamic effects.
• Non-equilibrium dynamics were analyzed concerning hydrodynamic interactions.
• Surface viscosity of the model membrane was measured and dissipative mechanisms discussed.

Conclusions:

• The proposed anisotropic Langevin dynamics framework effectively incorporates hydrodynamic coupling into coarse-grained membrane models.
• This approach enhances the realism of membrane simulations, enabling more accurate studies of biological processes.
• The method provides a balance between computational efficiency and physical accuracy for large-scale membrane dynamics.