{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,24]],"date-time":"2026-01-24T12:16:11Z","timestamp":1769256971859,"version":"3.49.0"},"reference-count":30,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T00:00:00Z","timestamp":1768953600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"crossref","award":["24-24-20074"],"award-info":[{"award-number":["24-24-20074"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Government of the Novosibirsk Region","award":["p-74"],"award-info":[{"award-number":["p-74"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>In this study, we constructed plasmids to increase the overall expression level of the SARS-CoV-2 S-protein and its presentation on the cell surface. To this end, we designed a series of plasmid constructs encoding the SARS-CoV-2 S-protein with modifications to its cytoplasmic domain and containing various 5\u2032 and 3\u2032 untranslated regions. Our results confirmed the critical role of the S-protein cytoplasmic domain in limiting its localization to the cell surface. We confirmed that deletion of the 19 C-terminal amino acids, which contain an endoplasmic reticulum retrieval signal, significantly increased S-protein presentation on the cell surface. Furthermore, introducing the HuR-binding site from the CD47 3\u2032 untranslated region and replacing the 19 C-terminal amino acids of the S-protein with the CD47 cytoplasmic tail significantly enhanced total S-protein expression compared to the wild-type S-protein and constructs with the 19-amino-acid deletion. Unfortunately, for the plasmid constructs bearing CD47 elements, their higher surface expression compared to the wild-type S-protein correlated with a high total protein expression level.<\/jats:p>","DOI":"10.3390\/v18010137","type":"journal-article","created":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T11:11:17Z","timestamp":1768993877000},"page":"137","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Introduction of a HuR-Binding Site in the 3\u2032 UTR and the CD47 Cytoplasmic Tail Enhances SARS-CoV-2 S-Protein Expression in Cells"],"prefix":"10.3390","volume":"18","author":[{"given":"Ivan M.","family":"Pereverzev","sequence":"first","affiliation":[{"name":"Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-8169-9871","authenticated-orcid":false,"given":"Irina A.","family":"Bakhno","sequence":"additional","affiliation":[{"name":"Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kristina I.","family":"Yakovleva","sequence":"additional","affiliation":[{"name":"Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6890-4538","authenticated-orcid":false,"given":"Ilya S.","family":"Dovydenko","sequence":"additional","affiliation":[{"name":"Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5201-7352","authenticated-orcid":false,"given":"Evgeniya E.","family":"Burkova","sequence":"additional","affiliation":[{"name":"Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5333","DOI":"10.1038\/s41467-021-25589-1","article-title":"Sequences in the cytoplasmic tail of SARS-CoV-2 Spike facilitate expression at the cell surface and syncytia formation","volume":"12","author":"Welch","year":"2021","journal-title":"Nat. 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