| Structural highlights
Function
SPIKE_SARS2 attaches the virion to the cell membrane by interacting with host receptor, initiating the infection (By similarity). Binding to human ACE2 receptor and internalization of the virus into the endosomes of the host cell induces conformational changes in the Spike glycoprotein (PubMed:32142651, PubMed:32075877, PubMed:32155444). Uses also human TMPRSS2 for priming in human lung cells which is an essential step for viral entry (PubMed:32142651). Proteolysis by cathepsin CTSL may unmask the fusion peptide of S2 and activate membranes fusion within endosomes.[HAMAP-Rule:MF_04099][1] [2] [3] mediates fusion of the virion and cellular membranes by acting as a class I viral fusion protein. Under the current model, the protein has at least three conformational states: pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. During viral and target cell membrane fusion, the coiled coil regions (heptad repeats) assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure appears to drive apposition and subsequent fusion of viral and target cell membranes.[HAMAP-Rule:MF_04099] Acts as a viral fusion peptide which is unmasked following S2 cleavage occurring upon virus endocytosis.[HAMAP-Rule:MF_04099]
Publication Abstract from PubMed
Antibodies with heavy chains that derive from the VH1-2 gene constitute some of the most potent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-neutralizing antibodies yet identified. To provide insight into whether these genetic similarities inform common modes of recognition, we determine the structures of the SARS-CoV-2 spike in complex with three VH1-2-derived antibodies: 2-15, 2-43, and H4. All three use VH1-2-encoded motifs to recognize the receptor-binding domain (RBD), with heavy-chain N53I-enhancing binding and light-chain tyrosines recognizing F486(RBD). Despite these similarities, class members bind both RBD-up and -down conformations of the spike, with a subset of antibodies using elongated CDRH3s to recognize glycan N343 on a neighboring RBD-a quaternary interaction accommodated by an increase in RBD separation of up to 12 A. The VH1-2 antibody class, thus, uses modular recognition encoded by modular genetic elements to effect potent neutralization, with the VH-gene component specifying recognition of RBD and the CDRH3 component specifying quaternary interactions.
Modular basis for potent SARS-CoV-2 neutralization by a prevalent VH1-2-derived antibody class.,Rapp M, Guo Y, Reddem ER, Yu J, Liu L, Wang P, Cerutti G, Katsamba P, Bimela JS, Bahna FA, Mannepalli SM, Zhang B, Kwong PD, Huang Y, Ho DD, Shapiro L, Sheng Z Cell Rep. 2021 Apr 6;35(1):108950. doi: 10.1016/j.celrep.2021.108950. Epub 2021 , Mar 19. PMID:33794145[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Wrapp D, Wang N, Corbett KS, Goldsmith JA, Hsieh CL, Abiona O, Graham BS, McLellan JS. Cryo-EM structure of the 2019-nCoV spike in the prefusion conformation. Science. 2020 Feb 19. pii: science.abb2507. doi: 10.1126/science.abb2507. PMID:32075877 doi:http://dx.doi.org/10.1126/science.abb2507
- ↑ Hoffmann M, Kleine-Weber H, Schroeder S, Kruger N, Herrler T, Erichsen S, Schiergens TS, Herrler G, Wu NH, Nitsche A, Muller MA, Drosten C, Pohlmann S. SARS-CoV-2 Cell Entry Depends on ACE2 and TMPRSS2 and Is Blocked by a Clinically Proven Protease Inhibitor. Cell. 2020 Apr 16;181(2):271-280.e8. doi: 10.1016/j.cell.2020.02.052. Epub 2020, Mar 5. PMID:32142651 doi:http://dx.doi.org/10.1016/j.cell.2020.02.052
- ↑ Walls AC, Park YJ, Tortorici MA, Wall A, McGuire AT, Veesler D. Structure, Function, and Antigenicity of the SARS-CoV-2 Spike Glycoprotein. Cell. 2020 Mar 6. pii: S0092-8674(20)30262-2. doi: 10.1016/j.cell.2020.02.058. PMID:32155444 doi:http://dx.doi.org/10.1016/j.cell.2020.02.058
- ↑ Rapp M, Guo Y, Reddem ER, Yu J, Liu L, Wang P, Cerutti G, Katsamba P, Bimela JS, Bahna FA, Mannepalli SM, Zhang B, Kwong PD, Huang Y, Ho DD, Shapiro L, Sheng Z. Modular basis for potent SARS-CoV-2 neutralization by a prevalent VH1-2-derived antibody class. Cell Rep. 2021 Apr 6;35(1):108950. PMID:33794145 doi:10.1016/j.celrep.2021.108950
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