Next Article in Journal
Equilibrium and Kinetics of Sin Nombre Hantavirus Binding at DAF/CD55 Functionalized Bead Surfaces
Next Article in Special Issue
Super-Resolution Microscopy: A Virus’ Eye View of the Cell
Previous Article in Journal
Acknowledgement to Reviewers of Viruses in 2013
Previous Article in Special Issue
The Tetraspanin CD151 in Papillomavirus Infection
Article Menu

Export Article

Open AccessCommunication
Viruses 2014, 6(3), 1078-1090; doi:10.3390/v6031078

Evidence Showing that Tetraspanins Inhibit HIV-1-Induced Cell-Cell Fusion at a Post-Hemifusion Stage

Graduate Program in Cell and Molecular Biology, University of Vermont, Burlington, VT 05405, USA
Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT 05405, USA
Author to whom correspondence should be addressed.
Received: 8 January 2014 / Revised: 14 February 2014 / Accepted: 20 February 2014 / Published: 7 March 2014
(This article belongs to the Special Issue Viruses and Tetraspanins)
View Full-Text   |   Download PDF [1415 KB, uploaded 12 May 2015]   |  


Human immunodeficiency virus type 1 (HIV-1) transmission takes place primarily through cell-cell contacts known as virological synapses. Formation of these transient adhesions between infected and uninfected cells can lead to transmission of viral particles followed by separation of the cells. Alternatively, the cells can fuse, thus forming a syncytium. Tetraspanins, small scaffolding proteins that are enriched in HIV-1 virions and actively recruited to viral assembly sites, have been found to negatively regulate HIV-1 Env-induced cell-cell fusion. How these transmembrane proteins inhibit membrane fusion, however, is currently not known. As a first step towards elucidating the mechanism of fusion repression by tetraspanins, e.g., CD9 and CD63, we sought to identify the stage of the fusion process during which they operate. Using a chemical epistasis approach, four fusion inhibitors were employed in tandem with CD9 overexpression. Cells overexpressing CD9 were found to be sensitized to inhibitors targeting the pre-hairpin and hemifusion intermediates, while they were desensitized to an inhibitor of the pore expansion stage. Together with the results of a microscopy-based dye transfer assay, which revealed CD9- and CD63-induced hemifusion arrest, our investigations strongly suggest that tetraspanins block HIV-1-induced cell-cell fusion at the transition from hemifusion to pore opening. View Full-Text
Keywords: tetraspanin; CD9; CD63; HIV; Env; cell-cell fusion; hemifusion tetraspanin; CD9; CD63; HIV; Env; cell-cell fusion; hemifusion

Figure 1

This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Symeonides, M.; Lambelé, M.; Roy, N.H.; Thali, M. Evidence Showing that Tetraspanins Inhibit HIV-1-Induced Cell-Cell Fusion at a Post-Hemifusion Stage. Viruses 2014, 6, 1078-1090.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Viruses EISSN 1999-4915 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top