title: Spatial organization of lipid phases in micropatterned polymer-supported membranes.
abstract: We have established an approach for the spatial control of lipid phase separation in tethered polymer-supported membranes (PSMs), which were obtained by vesicle fusion on a poly(ethylene glycol) polymer brush functionalized with fatty acid moieties. Phase separation of ternary lipid mixtures (1,2-dioleoyl-sn-glycero-3-phosphocholine/sphingomyelin/cholesterol) into liquid-disordered (l(d)) and liquid-ordered (l(o)) phases within both leaflets was obtained with palmitic acid as the anchoring group. In contrast, tethering of the PSM with oleic acid interfered with the phase separation in the surface-proximal leaflet. We exploited this feature for the assembly of l(o) domains within PSMs into defined structures by binary micropatterning of palmitic and oleic acid into complementary areas. Ternary lipid mixtures spontaneously separated into l(o) and l(d) phases controlled by the geometry of the underlying tethers. Transmembrane proteins reconstituted in these phase-separated PSMs strictly partitioned into the l(d) phase. Hence, the l(o) phase could be used for confining transmembrane proteins into microscopic and submicroscopic domains.
authors.affiliation: Division of Biophysics, Department of Biology, University of Osnabrück, 49069 Osnabrück, Germany.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Roder
authors.forename: Oliver
authors.initials: O
authors.lastname: Birkholz
authors.forename: Oliver
authors.initials: O
authors.lastname: Beutel
authors.forename: Dirk
authors.initials: D
authors.lastname: Paterok
authors.forename: Jacob
authors.initials: J
authors.lastname: Piehler
mesh_terms: D004058:Diffusion; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry*; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D008051:Lipid Bilayers; D008055:Lipids; D008565:Membrane Proteins; D011092:Polyethylene Glycols