Direction of actin flow dictates integrin LFA-1 orientation during leukocyte migration

Research output: Contribution to journalArticle

Abstract

Integrin αβ heterodimer cell surface receptors mediate adhesive interactions that provide traction for cell migration. Here, we test whether the integrin, when engaged to an extracellular ligand and the cytoskeleton, adopts a specific orientation dictated by the direction of actin flow on the surface of migrating cells. We insert GFP into the rigid, ligand-binding head of the integrin, model with Rosetta the orientation of GFP and its transition dipole relative to the integrin head, and measure orientation with fluorescence polarization microscopy. Cytoskeleton and ligand-bound integrins orient in the same direction as retrograde actin flow with their cytoskeleton-binding β-subunits tilted by applied force. The measurements demonstrate that intracellular forces can orient cell surface integrins and support a molecular model of integrin activation by cytoskeletal force. Our results place atomic, Å-scale structures of cell surface receptors in the context of functional and cellular, μm-scale measurements.

Details

Authors
  • Pontus Nordenfelt
  • Travis I Moore
  • Shalin B Mehta
  • Joseph Mathew Kalappurakkal
  • Vinay Swaminathan
  • Nobuyasu Koga
  • Talley J Lambert
  • David Baker
  • Jennifer C Waters
  • Rudolf Oldenbourg
  • Tomomi Tani
  • Satyajit Mayor
  • Clare M Waterman
  • Timothy A Springer
Organisations
External organisations
  • University of Washington, Seattle
  • Harvard Medical School
  • Marine Biological Laboratory
  • University of Washington
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Immunology in the medical area
Original languageEnglish
Article number2047
JournalNature Communications
Volume8
Issue number1
StatePublished - 2017 Dec 11
Publication categoryResearch
Peer-reviewedYes