Live-cell super-resolution reveals F-actin and plasma membrane dynamics at the T cell synapse

Research output: Contribution to journalArticle

Authors

  • George W. Ashdown
  • Garth L. Burn
  • David J. Williamson
  • Elvis Pandžić
  • Ruby Peters
  • Michael Holden
  • Helge Ewers
  • Lin Shao
  • Paul W. Wiseman

Colleges, School and Institutes

External organisations

  • Department of Immunology, Max Planck Institute for Infection Biology, Berlin, Germany.
  • Mark Wainwright Analytical Centre
  • Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
  • Advanced Imaging Center, Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, USA
  • Departments of Chemistry and Physics, McGill University
  • Department of Physics and Randall Division of Cell and Molecular Biophysics, King's College, London

Abstract

The cortical actin cytoskeleton has been shown to be critical for the reorganization and heterogeneity of plasma membrane components of many cells, including T cells. Building on previous studies at the T cell immunological synapse, we quantitatively assess the structure and dynamics of this meshwork using live-cell superresolution fluorescence microscopy and spatio-temporal image correlation spectroscopy. We show for the first time, to our knowledge, that not only does the dense actin cortex flow in a retrograde fashion toward the synapse center, but the plasma membrane itself shows similar behavior. Furthermore, using two-color, live-cell superresolution cross-correlation spectroscopy, we demonstrate that the two flows are correlated and, in addition, we show that coupling may extend to the outer leaflet of the plasma membrane by examining the flow of GPI-anchored proteins. Finally, we demonstrate that the actin flow is correlated with a third component, α-actinin, which upon CRISPR knockout led to reduced plasma membrane flow directionality despite increased actin flow velocity. We hypothesize that this apparent cytoskeletal-membrane coupling could provide a mechanism for driving the observed retrograde flow of signaling molecules such as the TCR, Lck, ZAP70, LAT, and SLP76.

Details

Original languageEnglish
Pages (from-to)1703-1713
Number of pages11
JournalBiophysical Journal
Volume112
Issue number8
Early online date25 Apr 2017
Publication statusPublished - 25 Apr 2017