Mechanical tension drives cell membrane fusion

Dev Cell. 2015 Mar 9;32(5):561-73. doi: 10.1016/j.devcel.2015.01.005. Epub 2015 Feb 12.

Abstract

Membrane fusion is an energy-consuming process that requires tight juxtaposition of two lipid bilayers. Little is known about how cells overcome energy barriers to bring their membranes together for fusion. Previously, we have shown that cell-cell fusion is an asymmetric process in which an "attacking" cell drills finger-like protrusions into the "receiving" cell to promote cell fusion. Here, we show that the receiving cell mounts a Myosin II (MyoII)-mediated mechanosensory response to its invasive fusion partner. MyoII acts as a mechanosensor, which directs its force-induced recruitment to the fusion site, and the mechanosensory response of MyoII is amplified by chemical signaling initiated by cell adhesion molecules. The accumulated MyoII, in turn, increases cortical tension and promotes fusion pore formation. We propose that the protrusive and resisting forces from fusion partners put the fusogenic synapse under high mechanical tension, which helps to overcome energy barriers for membrane apposition and drives cell membrane fusion.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Apoptosis
  • Blotting, Western
  • Cell Communication
  • Cell Membrane / metabolism*
  • Cell Proliferation
  • Cells, Cultured
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / growth & development
  • Drosophila melanogaster / metabolism*
  • Immunoenzyme Techniques
  • Immunoprecipitation
  • Lipid Bilayers / metabolism
  • Mechanotransduction, Cellular*
  • Membrane Fusion / physiology*
  • Models, Biological
  • Myosin Type II / genetics
  • Myosin Type II / metabolism*
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • rho GTP-Binding Proteins / genetics
  • rho GTP-Binding Proteins / metabolism
  • rho-Associated Kinases / genetics
  • rho-Associated Kinases / metabolism

Substances

  • Lipid Bilayers
  • RNA, Messenger
  • rho-Associated Kinases
  • Myosin Type II
  • rho GTP-Binding Proteins