Liquid immiscibility in model bilayer membranes: phase diagrams, critical
phenomena, and implications for lipid rafts

Abstract
Micron-scale liquid domains are easily produced in vesicles composed of
ternary mixtures of a high melting temperature lipid, a low melting
temperature lipid, and cholesterol. Similar systems are frequently studied
as models of raft domains in cell plasma membranes. In this seminar, I
will describe the rich phase behavior observed in binary and ternary lipid
systems, I will demonstrate that fluorescence microscopy and deuterium NMR
observations are consistent with a straight-forward thermodynamic
description of liquid immiscibility, and I will outline how this
understanding of the underlying phase diagram in model systems contributes
to the debate surrounding raft domains in cell membranes. Finally, I will
outline my current research in cellular systems aimed at understanding how
the physical properties of phase separation are utilized in biological
processes.