Lateral organization of complex lipid mixtures from multiscale modeling

摘要

The organizational properties of complex lipid mixtures can give rise to functionally importantstructures in cell membranes. In model membranes, ternary lipid-cholesterol (CHOL) mixtures areoften used as representative systems to investigate the formation and stabilization of localized structural domains ("rafts"). In this work, we describe a self-consistent mean-field model that buildson molecular dynamics simulations to incorporate multiple lipid components and to investigate the lateral organization of such mixtures. The model predictions reveal regions of bimodal order onternary plots that are in good agreement with experiment. Specifically, we have applied the model to ternary mixtures composed of dioleoylphosphatidylcholine:18:0 sphingomyelin:CHOL. Thiswork provides insight into the specific intermolecular interactions that drive the formation of localized domains in these mixtures. The model makes use of molecular dynamics simulations toextract interaction parameters and to provide chain configuration order parameter libraries.