Lipid domain formation and ligand-receptor distribution in lipid bilayer membranes investigated by atomic force microscopy.
A novel experimental technique, based on atomic force microscopy (AFM), is proposed to visualize the lateral organization of membrane systems in the nanometer range. The technique involves the use of a ligand-receptor pair, biotin-avidin, which introduces a height variation on a solid-supported lipid bilayer membrane. This leads to a height amplification of the lateral membrane organization that is large enough to be clearly imaged by scanning AFM. The power of the technique is demonstrated for a binary dipalmitoylphosphocholine-diarachidoylphosphocholine lipid mixture which is shown to exhibit a distinct lateral lipid domain formation. The new and simple ligand-receptor-based AFM approach opens up new ways to investigate lipid membrane microstructure in the nanometer range as well as the lateral distribution of ligand-lipid and receptor-protein complexes in supported membrane systems.
Kaasgaard
Thomas
T
Department of Chemistry, Technical University of Denmark, DK-2800, Lyngby, Denmark.
Mouritsen
Ole G
OG
Jørgensen
Kent
K
D001360:Avidin / Q000737:chemistry; D001710:Biotin / Q000737:chemistry; D008024:Ligands; D008051:Lipid Bilayers / Q000032:analysis / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry*; D046911:Macromolecular Substances; D021962:Membrane Microdomains / Q000737:chemistry*; D008567:Membranes, Artificial; D018625:Microscopy, Atomic Force / Q000379:methods*; D010767:Phosphorylcholine / Q000031:analogs & derivatives / Q000737:chemistry
D008024:Ligands; D008051:Lipid Bilayers; D008055:Lipids; D046911:Macromolecular Substances; D008567:Membranes, Artificial; D010767:Phosphorylcholine; D001360:Avidin; D001710:Biotin