Abstract
Coronavirus-cell entry programs involve virus-cell membrane fusions mediated by viral spike (S) proteins. Coronavirus S proteins acquire membrane fusion competence by receptor interactions, proteolysis, and acidification in endosomes. This review describes our current understanding of the S proteins, their interactions with and their responses to these entry triggers. We focus on receptors and proteases in prompting entry and highlight the type II transmembrane serine proteases (TTSPs) known to activate several virus fusion proteins. These and other proteases are essential cofactors permitting coronavirus infection, conceivably being in proximity to cell-surface receptors and thus poised to split entering spike proteins into the fragments that refold to mediate membrane fusion. The review concludes by noting how understanding of coronavirus entry informs antiviral therapies.
Keywords
ProteasesCoronavirusLipid bilayer fusionTransmembrane proteinViral entryBiologyMembrane proteinCell biologyViral membraneEndosomeReceptorVirologyBiochemistryCoronavirus disease 2019 (COVID-19)VirusMembraneViral replicationViral envelopeEnzyme
MeSH Terms
CoronavirusHumansMembrane GlycoproteinsSerine ProteasesSpike GlycoproteinCoronavirusViral Envelope ProteinsVirus Internalization
Affiliated Institutions
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Publication Info
- Year
- 2012
- Type
- review
- Volume
- 4
- Issue
- 4
- Pages
- 557-580
- Citations
- 349
- Access
- Closed
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Cite This
Taylor Heald‐Sargent,
Tom Gallagher
(2012).
Ready, Set, Fuse! The Coronavirus Spike Protein and Acquisition of Fusion Competence.
Viruses
, 4
(4)
, 557-580.
https://doi.org/10.3390/v4040557
Identifiers
- DOI
- 10.3390/v4040557
- PMID
- 22590686
- PMCID
- PMC3347323