Model membrane systems and their applications

Abstract

The complexity of biological membranes has motivated the development of a wide variety of simpler model systems whose size, geometry, and composition can be tailored with great precision. Approaches highlighted in this review are illustrated in Figure 1 including vesicles, supported bilayers, and hybrid membrane systems. These have been used to study problems ranging from phase behavior to membrane fusion. Experimental membrane models continue to advance in complexity with respect to architecture, size, and composition, as do computer simulations of their properties and dynamics. Analytical techniques such as imaging secondary ion mass spectrometry have also been developed and refined to give increasing spatial resolution and information content on membrane composition and dynamics.

Figure 1. Model membrane systems

A collection of model lipid membrane systems discussed in this review and surrounding a schematic diagram of a cell, drawn by Tomo Narashima, that emphasizes the large number of different membrane surfaces. In clockwise order, beginning from the upper left: (A) Giant unilamellar vesicles and blebs; (B) Networks of giant vesicles connected by lipid microtubules; (C) Ruptured GUV’s on solid supported bilayers; (D) Membrane nanodiscs containing transmembrane proteins; (E) Supported lipid bilayers analyzed by NanoSIMS; (F) Ruptured cell membranes on solid supports; (G) Bilayers tethered to a solid support containing ion channels; (H) Vesicles tethered to a supported lipid bilayer by DNA; (I) Visual representation of multi-scale simulations.