title: Direct observation of ligand colocalization on individual receptor molecules.
abstract: We have exploited the novel methodology of far-field fluorescence microscopy at the single molecule level to study colocalization of two different ligand molecules on an individual receptor. The use of dual-wavelength single molecule imaging allows discrimination between isolated and colocalized ligands with an accuracy of 40 nm. In the case of very close proximity of the two ligands, below 7 nm, single pair Forster energy-transfer was observed. The latter finding unequivocally demonstrates colocalization of two ligands on an individual receptor.
authors.affiliation: Institute for Biophysics, University of Linz, Austria.
authors.forename: G J
authors.initials: GJ
authors.lastname: Schütz
authors.forename: W
authors.initials: W
authors.lastname: Trabesinger
authors.forename: T
authors.initials: T
authors.lastname: Schmidt
mesh_terms: D001665:Binding Sites; D001710:Biotin / Q000737:chemistry*; D004134:Dimyristoylphosphatidylcholine; D004735:Energy Transfer; D008024:Ligands; D008856:Microscopy, Fluorescence / Q000379:methods; D008954:Models, Biological; D008958:Models, Molecular; D011956:Receptors, Cell Surface / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019809:Streptavidin / Q000737:chemistry*
chemical_list: D008024:Ligands; D011956:Receptors, Cell Surface; D001710:Biotin; D019809:Streptavidin; D004134:Dimyristoylphosphatidylcholine