Liquid-liquid phase separation has emerged as a fundamental mechanism
underlying intracellular organization, with evidence for it being reported in
numerous different systems. However, there is a growing concern regarding the
lack of quantitative rigor in the techniques employed to study phase
separation, and their ability to account for the complex nature of the cellular
milieu, which affects key experimentally observable measures, such as the
shape, size and transport dynamics of liquid droplets. Here we bridge this gap
by combining recent experimental data with theoretical predictions that capture
the subtleties of nonlinear elasticity and fluid transport. We show that within
a biologically accessible range of material parameters, phase separation is
highly sensitive to elastic properties and can thus be used as a mechanical
switch to rapidly transition between different states in cellular systems.
Furthermore, we show that this active mechanically mediated mechanism can drive
transport across cells at biologically relevant timescales and could play a
crucial role in promoting spatial localization of condensates; whether cells
exploit such mechanisms for transport of their constituents, remains an open
question.
