title: Dynamic submicroscopic signaling zones revealed by pair correlation tracking and localization microscopy.
abstract: Unraveling the spatiotemporal organization of signaling complexes within the context of plasma membrane nanodomains has remained a highly challenging task. Here, we have applied super-resolution image correlation based on tracking and localization microscopy (TALM) for probing transient confinement as well as ligand binding and intracellular effector recruitment of the type I interferon (IFN) receptor in the plasma membrane of live cells. Ligand and receptor were labeled with monofunctional quantum dots, thus allowing long-term tracking with very high spatial and temporal resolution without an artificial receptor cross-linking at the cell surface. Dual-color TALM was employed for visualizing protein-protein interactions involved in IFN signaling at both sides of the plasma membrane with high spatial and temporal resolution. By pair correlation analyses based on time-lapse TALM images (pcTALM), complex assembly within dynamic submicroscopic zones was identified. Strikingly, recruitment of the IFN effector protein signal transducer and activator of transcription 2 (STAT2) into these dynamic signaling zones could be observed. The results suggest that confined diffusion zones in the plasma membrane are employed as transient platforms for the assembly of signaling complexes.
authors.affiliation: Department of Biology, University of Osnabrück , Barbarastrasse 11, 49076 Osnabrück, Germany.
authors.forename: Changjiang
authors.initials: C
authors.lastname: You
authors.forename: Christian P
authors.initials: CP
authors.lastname: Richter
authors.forename: Sara
authors.initials: S
authors.lastname: Löchte
authors.forename: Stephan
authors.initials: S
authors.lastname: Wilmes
authors.forename: Jacob
authors.initials: J
authors.lastname: Piehler
mesh_terms: D001710:Biotin / Q000737:chemistry / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism; D060066:Protein Interaction Maps; D045663:Quantum Dots / Q000737:chemistry; D053633:Receptor, Interferon alpha-beta / Q000235:genetics / Q000378:metabolism*; D050795:STAT2 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction; D059008:Time-Lapse Imaging
chemical_list: C508033:IFNAR2 protein, human; D009842:Oligopeptides; D050795:STAT2 Transcription Factor; D053633:Receptor, Interferon alpha-beta; D001710:Biotin; C047981:arginyl-glycyl-aspartic acid