03.05.2022 - John E. Straub "Probing the mechanism of phase separation and domain formation in ternary lipid bilayers"

The phase separation of lipid mixtures into liquid ordered and liquid disordered domains has been conjectured to play an essential role in cellular organization and function. Extensive study using experiment, simulation, and theory has led to a good understanding of the thermodynamics of this transition, including the effect of finite system size on the transition.  However, relatively little is known about the kinetic mechanism underlying this process.  We report on extended non-equilibrium dynamical simulations of phase separation in a ternary lipid mixture, using both coarse-grained and all-atom models.  Analysis applied to phase separation in binary mixtures is used to gain insight into the dynamical phases underlying this process, including curious differences between the predictions of the coarse-grained and all-atom representations.  Critical areas for future experimental and simulation studies are noted.