Diffusion Effects in Cross-Linked Bilayers

Abstract

We investigate peptide interactions with model membranes and how they affect phase dynamics and mobility. Previously, we have studied lipid phase rearrangement due to cross-linking lipids in the headgroup position. Clustering and possible subanomalous diffusion inhibit domain coalescence and alter the conformation energy minimum. Building on this, our current efforts investigate peptide perturbations in lipid bilayers. We cross-link transmembrane peptides on the surface of lipid vesicles to examine the interactions between the helices, mimicking B cell receptor clustering. We conduct these studies by modifying the transmembrane portion of the mIgM receptor and incorporating the resulting peptide into the bilayer. We analyze these associations using microscopy, FRAP, FRET and CD spectroscopy.