{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T03:14:59Z","timestamp":1790997299464,"version":"4.1.0"},"reference-count":149,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,2,21]],"date-time":"2021-02-21T00:00:00Z","timestamp":1613865600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100001117","name":"amfAR, The Foundation for AIDS Research","doi-asserted-by":"publisher","award":["109998-67-RKVA"],"award-info":[{"award-number":["109998-67-RKVA"]}],"id":[{"id":"10.13039\/100001117","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>As a major surface glycoprotein of enveloped viruses, the virus spike protein is a primary target for vaccines and anti-viral treatments. Current vaccines aiming at controlling the COVID-19 pandemic are mostly directed against the SARS-CoV-2 spike protein. To promote virus entry and facilitate immune evasion, spikes must be dynamic. Interactions with host receptors and coreceptors trigger a cascade of conformational changes\/structural rearrangements in spikes, which bring virus and host membranes in proximity for membrane fusion required for virus entry. Spike-mediated viral membrane fusion is a dynamic, multi-step process, and understanding the structure\u2013function-dynamics paradigm of virus spikes is essential to elucidate viral membrane fusion, with the ultimate goal of interventions. However, our understanding of this process primarily relies on individual structural snapshots of endpoints. How these endpoints are connected in a time-resolved manner, and the order and frequency of conformational events underlying virus entry, remain largely elusive. Single-molecule F\u00f6rster resonance energy transfer (smFRET) has provided a powerful platform to connect structure\u2013function in motion, revealing dynamic aspects of spikes for several viruses: SARS-CoV-2, HIV-1, influenza, and Ebola. This review focuses on how smFRET imaging has advanced our understanding of virus spikes\u2019 dynamic nature, receptor-binding events, and mechanism of antibody neutralization, thereby informing therapeutic interventions.<\/jats:p>","DOI":"10.3390\/v13020332","type":"journal-article","created":{"date-parts":[[2021,2,21]],"date-time":"2021-02-21T23:59:31Z","timestamp":1613951971000},"page":"332","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Single-Molecule FRET Imaging of Virus Spike\u2013Host Interactions"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8099-6447","authenticated-orcid":false,"given":"Maolin","family":"Lu","sequence":"first","affiliation":[{"name":"Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06536, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"690","DOI":"10.1038\/nsmb.1456","article-title":"Viral membrane fusion","volume":"15","author":"Harrison","year":"2008","journal-title":"Nat. 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