Long-range interactions between membrane inclusions: Electric field induced giant amplification of the pairwise potential

TL;DR

This paper explores how external electric fields can significantly amplify the interactions between membrane inclusions, such as proteins and RNA, by introducing a new coupling mechanism that enhances pairwise potentials.

Contribution

It introduces a novel coupling mechanism driven by electric fields that causes giant amplification of membrane inclusion interactions, expanding the understanding of membrane fluctuation-mediated forces.

Findings

Electric fields induce a new coupling mechanism.

Giant enhancement of pairwise potential observed.

Potential for controlling membrane interactions externally.

Abstract

The aim of this work is to revisit the phenomenological theory of the interaction between membrane inclusions, mediated by the membrane fluctuations. We consider the case where the inclusions are separated by distances larger than their characteristic size. Within our macroscopic approach a physical nature of such inclusions is not essential, however we have always in mind two prototypes of such inclusions: proteins and RNA macromolecules. Because the interaction is driven by the membrane fluctuations, and the coupling between inclusions and the membrane, it is possible to change the interaction potential by external actions affecting these factors. As an example of such external action we consider an electric field. Under external electric field (both dc or ac), we propose a new coupling mechanism between inclusions possessing dipole moments (as it is the case for most protein macromolecules) and the membrane. We found, quite unexpected and presumably for the first time, that the new coupling mechanism yields to giant enhancement of the pairwise potential of the inclusions. This result opens up a way to handle purposefully the interaction energy, and as well to test of the theory set forth in our article.