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Updated: Aug 16, 2026

Visualization of HIV-1 Gag Binding to Giant Unilamellar Vesicle (GUV) Membranes
Published on: July 28, 2016
Involvement of a small GTP binding protein in HIV-1 release
Gilles Audoly1, Michel R Popoff, Pablo Gluschankof
1Unité des Rickettsies, CNRS UMR6020, Faculté de Médecine, 27 bd Jean Moulin, 13385 Marseille cedex 05, IFR48, France. gilles.audoly@medecine.univ-mrs.fr
Background:
There is evidence suggesting that actin binding to HIV-1 encoded proteins, or even actin dynamics themselves, might play a key role in virus budding and/or release from the infected cell. A crucial step in the reorganisation of the actin cytoskeleton is the engagement of various different GTP binding proteins. We have thus studied the involvement of GTP-binding proteins in the final steps of the HIV-1 viral replication cycle.
Results:
Our results demonstrate that virus production is abolished when cellular GTP binding proteins involved in actin polymerisation are inhibited with specific toxins.
Conclusion:
We propose a new HIV budding working model whereby Gag interactions with pre-existing endosomal cellular tracks as well as with a yet non identified element of the actin polymerisation pathway are required in order to allow HIV-1 to be released from the infected cell.
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