Conformational dynamics of single HIV-1 envelope trimers on the surface of native virions

Science. 2014 Nov 7;346(6210):759-63. doi: 10.1126/science.1254426. Epub 2014 Oct 8.


The HIV-1 envelope (Env) mediates viral entry into host cells. To enable the direct imaging of conformational dynamics within Env, we introduced fluorophores into variable regions of the glycoprotein gp120 subunit and measured single-molecule fluorescence resonance energy transfer within the context of native trimers on the surface of HIV-1 virions. Our observations revealed unliganded HIV-1 Env to be intrinsically dynamic, transitioning between three distinct prefusion conformations, whose relative occupancies were remodeled by receptor CD4 and antibody binding. The distinct properties of neutralization-sensitive and neutralization-resistant HIV-1 isolates support a dynamics-based mechanism of immune evasion and ligand recognition.

Publication types

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

MeSH terms

  • Antibodies, Neutralizing / immunology
  • CD4 Antigens / immunology
  • Fluorescence Resonance Energy Transfer / methods
  • HIV Envelope Protein gp120 / chemistry*
  • HIV Envelope Protein gp120 / immunology
  • HIV-1 / chemistry*
  • HIV-1 / immunology
  • Humans
  • Immune Evasion*
  • Ligands
  • Models, Chemical
  • Molecular Imaging / methods
  • Protein Multimerization
  • Protein Structure, Tertiary
  • Virion / chemistry*
  • Virion / immunology


  • Antibodies, Neutralizing
  • CD4 Antigens
  • HIV Envelope Protein gp120
  • Ligands