Binding and dimerization control phase separation in a compartment

TL;DR

This paper investigates how binding, dimerization, and oligomerization influence phase separation in cellular compartments, revealing that oligomerization amplifies compartment formation and can induce multistability, offering insights into cellular regulation mechanisms.

Contribution

It introduces an equilibrium model showing that oligomerization enhances phase separation and multistability, providing a foundation for thermodynamically consistent kinetic models of cellular compartment regulation.

Findings

Oligomerization amplifies phase separation.

Multistability can be induced by nonlinear interactions.

The model offers a basis for kinetic modeling of cellular regulation.

Abstract

Biological cells exhibit a hierarchical spatial organization, where various compartments harbor condensates that form by phase separation. Cells can control the emergence of these condensates by affecting compartment size, the amount of the involved molecules, and their physical interactions. While physical interactions directly affect compartment binding and phase separation, they can also cause oligomerization, which has been suggested as a control mechanism. Analyzing an equilibrium model, we illustrate that oligomerization amplifies compartment binding and phase separation, which reinforce each other. This nonlinear interplay can also induce multistability, which provides additional potential for control. Our work forms the basis for deriving thermodynamically consistent kinetic models to understand how biological cells can regulate phase separation in their compartments.