ArticleJournal of virology2009
Two-step conformational changes in a coronavirus envelope glycoprotein mediated by receptor binding and proteolysis.
Article in Journal of virology, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 72 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
72 citing papers in PubMed, 95 citations in OpenAlex.
- Mechanisms of antibody-dependent enhancement and its research progress in animal coronaviruses.Veterinary research · 2026Review
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- TMPRSS2-mediated coronavirus spike activation and inhibition.Nature structural & molecular biology · 2026Article
- Mutations to the HCoV-229E spike have counterbalancing effects on serum antibody neutralization and receptor binding.bioRxiv : the preprint server for biology · 2026Article
- A broadly neutralizing antibody recognizes a unique epitope with a signature motif common across coronaviruses.Nature communications · 2025Article
- Article
- Synergistic activation of bat SARS-like coronaviruses spike protein by elastase and TMPRSS2.Scientific reports · 2025Article
- Dexamethasone disrupts intracellular pH homeostasis to delay coronavirus infectious bronchitis virus cell entry via sodium hydrogen exchanger 3 activation.Journal of virology · 2025Article
- Review
- Article
- Antibodies utilizing VL6-57 light chains target a convergent cryptic epitope on SARS-CoV-2 spike protein and potentially drive the genesis of Omicron variants.Nature communications · 2024Article
- Structure defining of ultrapotent neutralizing nanobodies against MERS-CoV with novel epitopes on receptor binding domain.PLoS pathogens · 2024Article
- Adaptive variations in SARS-CoV-2 spike proteins: effects on distinct virus-cell entry stages.mBio · 2023Article
- Construction and immunogenicity of a trypsin-independent porcine epidemic diarrhea virus variant.Frontiers in immunology · 2023Article
- SARS-CoV-2 Delta and Omicron variants evade population antibody response by mutations in a single spike epitope.Nature microbiology · 2022Article
- Two Years into the COVID-19 Pandemic: Lessons Learned.ACS infectious diseases · 2022Review
- Towards Label-free detection of viral disease agents through their cell surface proteins: Rapid screening SARS-CoV-2 in biological specimens.SLAS discovery : advancing life sciences R & D · 2022Article
- Article
- Inter-domain communication in SARS-CoV-2 spike proteins controls protease-triggered cell entry.Cell reports · 2022Article
- SARS-CoV-2 spike engagement of ACE2 primes S2' site cleavage and fusion initiation.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
12 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The coronaviruses mouse hepatitis virus type 2 (MHV-2) and severe acute respiratory syndrome coronavirus (SARS-CoV) utilize proteases to enter host cells. Upon receptor binding, the spike (S) proteins of both viruses are activated for membrane fusion by proteases, such as trypsin, present in the environment, facilitating virus entry from the cell surface. In contrast, in the absence of extracellular proteases, these viruses can enter cells via an endosomal pathway and utilize endosomal cathepsins for S protein activation. We demonstrate that the MHV-2 S protein uses multistep conformational changes for membrane fusion. After interaction with a soluble form of the MHV receptor (CEACAM1a), the metastable form of S protein is converted to a stable trimer, as revealed by mildly denaturing sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Liposome-binding assays indicate that the receptor-bound virions are associated with the target membrane through hydrophobic interactions. The exposure of receptor-bound S protein to trypsin or cathepsin L (CPL) induces the formation of six-helix bundles (6HB), the final conformation. This trypsin- or CPL-mediated conversion to 6HB can be blocked by a heptad repeat peptide known to block the formation of 6HB. Although trypsin treatment enabled receptor-bound MHV-2 to enter from the cell surface, CPL failed to do so. Interestingly, consecutive treatment with CPL and then chlorpromazine enabled a portion of the virus to enter from cell surface. These results suggest that trypsin suffices for the induction of membrane fusion of receptor-primed S protein, but an additional unidentified cellular factor is required to trigger membrane fusion by CPL.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.