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Real-Time Analysis of Individual Ebola Virus Glycoproteins Reveals Pre-Fusion, Entry-Relevant Conformational Dynamics
Authors
Durham, Natasha D.Howard, Angela R.
Govindan, Ramesh
Senjobe, Fernando
Fels, J. Maximilian
Diehl, William E
Luban, Jeremy
Chandran, Kartik
Munro, James B
UMass Chan Affiliations
Program in Molecular MedicineDepartment of Microbiology and Physiological Systems
Document Type
Journal ArticlePublication Date
2020-01-15Keywords
Ebola virusconformational dynamics
envelope glycoprotein
single-molecule FRET
virus entry
Amino Acids, Peptides, and Proteins
Biochemistry, Biophysics, and Structural Biology
Virology
Virus Diseases
Viruses
Metadata
Show full item recordAbstract
The Ebola virus (EBOV) envelope glycoprotein (GP) mediates the fusion of the virion membrane with the membrane of susceptible target cells during infection. While proteolytic cleavage of GP by endosomal cathepsins and binding of the cellular receptor Niemann-Pick C1 protein (NPC1) are essential steps for virus entry, the detailed mechanisms by which these events promote membrane fusion remain unknown. Here, we applied single-molecule Forster resonance energy transfer (smFRET) imaging to investigate the structural dynamics of the EBOV GP trimeric ectodomain, and the functional transmembrane protein on the surface of pseudovirions. We show that in both contexts, pre-fusion GP is dynamic and samples multiple conformations. Removal of the glycan cap and NPC1 binding shift the conformational equilibrium, suggesting stabilization of conformations relevant to viral fusion. Furthermore, several neutralizing antibodies enrich alternative conformational states. This suggests that these antibodies neutralize EBOV by restricting access to GP conformations relevant to fusion. This work demonstrates previously unobserved dynamics of pre-fusion EBOV GP and presents a platform with heightened sensitivity to conformational changes for the study of GP function and antibody-mediated neutralization.Source
Durham ND, Howard AR, Govindan R, Senjobe F, Fels JM, Diehl WE, Luban J, Chandran K, Munro JB. Real-Time Analysis of Individual Ebola Virus Glycoproteins Reveals Pre-Fusion, Entry-Relevant Conformational Dynamics. Viruses. 2020 Jan 15;12(1):E103. doi: 10.3390/v12010103. PMID: 31952255. Link to article on publisher's site
DOI
10.3390/v12010103Permanent Link to this Item
http://hdl.handle.net/20.500.14038/41366PubMed ID
31952255Related Resources
Rights
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Distribution License
http://creativecommons.org/licenses/by/4.0/ae974a485f413a2113503eed53cd6c53
10.3390/v12010103
Scopus Count
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Except where otherwise noted, this item's license is described as © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
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