Mutagenesis of the transmembrane domain of the SARS coronavirus spike glycoprotein: refinement of the requirements for SARS coronavirus cell entry
Open Access
- 24 December 2009
- journal article
- Published by Springer Science and Business Media LLC in Virology Journal
- Vol. 6 (1), 230
- https://doi.org/10.1186/1743-422x-6-230
Abstract
The spike protein (S) of SARS Coronavirus (SARS-CoV) mediates entry of the virus into target cells, including receptor binding and membrane fusion. Close to or in the viral membrane, the S protein contains three distinct motifs: a juxtamembrane aromatic part, a central highly hydrophobic stretch and a cysteine rich motif. Here, we investigate the role of aromatic and hydrophobic parts of S in the entry of SARS CoV and in cell-cell fusion. This was investigated using the previously described SARS pseudotyped particles system (SARSpp) and by fluorescence-based cell-cell fusion assays. Mutagenesis showed that the aromatic domain was crucial for SARSpp entry into cells, with a likely role in pore enlargement.Introduction of lysine residues in the hydrophobic stretch of S also resulted in a block of entry, suggesting the borders of the actual transmembrane domain. Surprisingly, replacement of a glycine residue, situated close to the aromatic domain, with a lysine residue was tolerated, whereas the introduction of a lysine adjacent to the glycine, was not. In a model, we propose that during fusion, the lateral flexibility of the transmembrane domain plays a critical role, as do the tryptophans and the cysteines. The aromatic domain plays a crucial role in the entry of SARS CoV into target cells. The positioning of the aromatic domain and the hydrophobic domain relative to each other is another essential characteristic of this membrane fusion process.Keywords
This publication has 34 references indexed in Scilit:
- Importance of SARS-CoV spike protein Trp-rich region in viral infectivityBiochemical and Biophysical Research Communications, 2008
- Lipid rafts are involved in SARS-CoV entry into Vero E6 cellsBiochemical and Biophysical Research Communications, 2008
- Aromatic Amino Acids in the Juxtamembrane Domain of Severe Acute Respiratory Syndrome Coronavirus Spike Glycoprotein Are Important for Receptor-Dependent Virus Entry and Cell-Cell FusionJournal of Virology, 2008
- GxxxG Motif of Severe Acute Respiratory Syndrome Coronavirus Spike Glycoprotein Transmembrane Domain Is Not Involved in Trimerization and Is Not Important for EntryJournal of Virology, 2007
- The Cytoplasmic Tail of the Severe Acute Respiratory Syndrome Coronavirus Spike Protein Contains a Novel Endoplasmic Reticulum Retrieval Signal That Binds COPI and Promotes Interaction with Membrane ProteinJournal of Virology, 2007
- Architecture of the SARS coronavirus prefusion spikeNature Structural & Molecular Biology, 2006
- A Synergistic Effect between Cholesterol and Tryptophan-Flanked Transmembrane Helices Modulates Membrane CurvatureBiochemistry, 2005
- Peptide-Induced Formation of Cholesterol-Rich DomainsBiochemistry, 2003
- Multiple Local Contact Sites are Induced by GPI‐Linked Influenza Hemagglutinin During Hemifusion and Flickering Pore FormationTraffic, 2000
- GPI-anchored influenza hemagglutinin induces hemifusion to both red blood cell and planar bilayer membranes.The Journal of cell biology, 1995