Fluctuation spectrum of quasispherical membranes with force-dipole activity

TL;DR

This paper calculates the fluctuation spectrum of quasi-spherical vesicles with active proteins, considering both thermal and active force contributions, revealing significant noise effects at short wavelengths.

Contribution

It introduces a model incorporating non-local active force distributions and noise in active forces, advancing understanding of membrane fluctuation spectra with activity.

Findings

Active force noise becomes significant at short wavelengths.

Thermal and active protein fluctuations both influence membrane behavior.

The model captures non-local force effects in membrane dynamics.

Abstract

The fluctuation spectrum of a quasi-spherical vesicle with active membrane proteins is calculated. The activity of the proteins is modeled as the proteins pushing on their surroundings giving rise to non-local force distributions. Both the contributions from the thermal fluctuations of the active protein densities and the temporal noise in the individual active force distributions of the proteins are taken into account. The noise in the individual force distributions is found to become significant at short wavelengths.