Morphology of axisymmetric vesicles with encapsulated filaments and impurities

TL;DR

This paper investigates the shape changes of axisymmetric vesicles with encapsulated filaments or impurities using a dissipation dynamics approach, revealing phase transitions and shape evolution through simulations and stability analysis.

Contribution

It introduces a systematic method to analyze vesicle shape deformation with encapsulated structures and impurities, including phase diagrams and dynamic evolution insights.

Findings

Phase diagrams of vesicle shape transitions.

Linear stability analysis explains early shape deformation.

Nonlinear coarsening observed in late-stage dynamics.

Abstract

The shape deformation of a three-dimensional axisymmetric vesicle with encapsulated filaments or impurities is analyzed by integrating a dissipation dynamics. This method can incorporate systematically the constraint of a fixed surface area and/or a fixed volume. The filament encapsulated in a vesicle is assumed to take a form of a rod or a ring so as to imitate cytoskeletons. In both cases, results of the shape transition of the vesicle are summarized in phase diagrams in the phase space of the vesicular volume and a rod length or a ring radius. We also study the dynamics of a vesicle with impurities coupled to the membrane curvature. The phase separation and the associated shape deformation in the early stage of the dynamical evolution can well be explained by the linear stability analysis. Long runs of simulation demonstrate the nonlinear coarsening of the wavy deformation of the vesicle in the late stage.