title: Ratiometric Tension Probes for Mapping Receptor Forces and Clustering at Intermembrane Junctions.
abstract: Short-range communication between cells is required for the survival of multicellular organisms. One mechanism of chemical signaling between adjacent cells employs surface displayed ligands and receptors that only bind when two cells make physical contact. Ligand-receptor complexes that form at the cell-cell junction and physically bridge two cells likely experience mechanical forces. A fundamental challenge in this area pertains to mapping the mechanical forces experienced by ligand-receptor complexes within such a fluid intermembrane junction. Herein, we describe the development of ratiometric tension probes for direct imaging of receptor tension, clustering, and lateral transport within a model cell-cell junction. These probes employ two fluorescent reporters that quantify both the ligand density and the ligand tension and thus generate a tension signal independent of clustering. As a proof-of-concept, we applied the ratiometric tension probes to map the forces experienced by the T-cell receptor (TCR) during activation and showed the first direct evidence that the TCR-ligand complex experiences sustained pN forces within a fluid membrane junction. We envision that the ratiometric tension probes will be broadly useful for investigating mechanotransduction in juxtacrine signaling pathways.
authors.affiliation: Department of Chemistry, Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Victor Pui-Yan
authors.initials: VP
authors.lastname: Ma
authors.affiliation: Department of Chemistry, Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Microbiology and Immunology, Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Lori
authors.initials: L
authors.lastname: Blanchfield
authors.affiliation: Department of Chemistry, Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Hanquan
authors.initials: H
authors.lastname: Su
authors.affiliation: Department of Microbiology and Immunology, Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Evavold
authors.affiliation: Department of Chemistry, Emory University , Atlanta, Georgia 30322, United States.|Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Khalid
authors.initials: K
authors.lastname: Salaita
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000502:physiology*; D005456:Fluorescent Dyes; D006046:Gold; D061925:Immobilized Nucleic Acids; D008024:Ligands; D040542:Mechanotransduction, Cellular; D053768:Metal Nanoparticles; D008822:Mice, Transgenic; D011948:Receptors, Antigen, T-Cell / Q000737:chemistry*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000166:cytology
chemical_list: D005456:Fluorescent Dyes; D061925:Immobilized Nucleic Acids; D008024:Ligands; D011948:Receptors, Antigen, T-Cell; D006046:Gold
keywords: Receptor clustering; T-cell; artificial antigen presenting cell; immunological synapse; intermembrane junction; molecular tension probe