Membrane and Receptor Biology:
Our interests center around the structure and function of cell membranes, receptor-ligand interactions and transmembrane signaling mechanisms. A combination of biochemical, chemical and biophysical approaches are used to probe: (1) membrane lipid conformation, structure, properties and interactions, (2) membrane receptor-lipid interactions and (3) membrane receptor-ligand interactions. Current approaches involve the isolation of membrane-associated proteins and lipids (e.g. low density lipoprotein (LDL) receptor, insulin receptor, integrins, gangliosides), their reconstitution with well characterized lipid monolayer and bilayer matrices and structural studies of the protein-lipid assemblies. Ligand binding studes include LDL receptor/LDL, insulin receptor/insulin, and ganglioside/toxin interactions. The biochemical methods involved include lipid and protein isolation, gel/affinity chromatography, antibody techniques, immunoblotting, detergent solubilization, lipid-protein reconstitution, etc. Chemical methods include lipid sythesis, TLC, HPLC, IR and NMR. The biophysical approach involves x-ray diffraction, protein crystallography, electron microscopy/image reconstruction, surface chemistry and calorimetric and spectroscopic (CD, NMR) methods.