title: Electrostatically controlled quantum dot monofunctionalization for interrogating the dynamics of protein complexes in living cells.
abstract: Quantum dots (QD) are powerful labels for probing diffusion and interaction dynamics of proteins on the single molecule level in living cells. Protein cross-linking due to multifunctional QD strongly affects these properties. This becomes particularly critical when labeling interaction partners with QDs for interrogating the dynamics of complexes. We have here implemented a generic method for QD monofunctionalization based on electrostatic repulsion of a highly negatively charged peptide carrier. On the basis of this method, monobiotinylated QDs were prepared with high yield as confirmed by single molecule assays. These QDs were successfully employed for probing the assembly and diffusion dynamics of binary and ternary cytokine-receptor complexes on the surface of living cells by dual color single QD tracking. Thus, sequential and dynamic recruitment of the type I interferon receptor subunits by the ligand could be observed.
authors.affiliation: Division of Biophysics, Department of Biology, University of Osnabrück, 49076 Osnabrück, Germany. you@biologie.uni-osnabrueck.de
authors.forename: Changjiang
authors.initials: C
authors.lastname: You
authors.forename: Stephan
authors.initials: S
authors.lastname: Wilmes
authors.forename: Christian P
authors.initials: CP
authors.lastname: Richter
authors.forename: Oliver
authors.initials: O
authors.lastname: Beutel
authors.forename: Domenik
authors.initials: D
authors.lastname: Liße
authors.forename: Jacob
authors.initials: J
authors.lastname: Piehler
mesh_terms: D006367:HeLa Cells; D006801:Humans; D008954:Models, Biological; D015394:Molecular Structure; D046912:Multiprotein Complexes / Q000737:chemistry / Q000378:metabolism*; D045663:Quantum Dots; D053633:Receptor, Interferon alpha-beta / Q000737:chemistry / Q000378:metabolism*; D055672:Static Electricity
chemical_list: D046912:Multiprotein Complexes; D053633:Receptor, Interferon alpha-beta