Multiple stalk formation as a pathway of defect-induced membrane fusion

TL;DR

This paper proposes a new model for membrane fusion where multiple stalks form cooperatively due to defect interactions, leading to a dense fusion intermediate, challenging the traditional single-stalk hypothesis.

Contribution

It introduces a defect-induced fusion pathway involving multiple stalks and membrane-mediated interactions, expanding understanding of membrane fusion mechanisms.

Findings

Defects attract each other via membrane-mediated capillary interactions.

Multiple stalk formation leads to a dense fusion intermediate.

Fusion proceeds through a cooperative condensation transition of stalks.

Abstract

We propose that the first stage of membrane fusion need not be the formation of a single stalk. Instead, we consider a scenario for defect-induced membrane fusion that proceeds cooperatively via multiple stalk formation. The defects (stalks or pores) attract each other via membrane-mediated capillary interactions that result in a condensation transition of the defects. The resulting dense phase of stalks corresponds to the so-called fusion intermediate.