{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T06:16:01Z","timestamp":1771049761613,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,10,12]],"date-time":"2022-10-12T00:00:00Z","timestamp":1665532800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie","award":["813453"],"award-info":[{"award-number":["813453"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Adaptive laboratory evolution has been used to improve production of influenza hemagglutinin (HA)-displaying virus-like particles (VLPs) in insect cells. However, little is known about the underlying biological mechanisms promoting higher HA-VLP expression in such adapted cell lines. In this article, we present a study of gene expression patterns associated with high-producer insect High Five cells adapted to neutral pH, in comparison to non-adapted cells, during expression of influenza HA-VLPs. RNA-seq shows a decrease in the amount of reads mapping to host cell genomes along infection, and an increase in those mapping to baculovirus and transgenes. A total of 1742 host cell genes were found differentially expressed between adapted and non-adapted cells throughout infection, 474 of those being either up- or down-regulated at both time points evaluated (12 and 24 h post-infection). Interestingly, while host cell genes were found up- and down-regulated in an approximately 1:1 ratio, all differentially expressed baculovirus genes were found to be down-regulated in infected adapted cells. Pathway analysis of differentially expressed genes revealed enrichment of ribosome biosynthesis and carbohydrate, amino acid, and lipid metabolism. In addition, oxidative phosphorylation and protein folding, sorting and degradation pathways were also found to be overrepresented. These findings contribute to our knowledge of biological mechanisms of insect cells during baculovirus-mediated transient expression and will assist the identification of potential engineering targets to increase recombinant protein production in the future.<\/jats:p>","DOI":"10.3390\/v14102238","type":"journal-article","created":{"date-parts":[[2022,10,12]],"date-time":"2022-10-12T22:45:29Z","timestamp":1665614729000},"page":"2238","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Gene Expression Analysis of Adapted Insect Cells during Influenza VLP Production Using RNA-Sequencing"],"prefix":"10.3390","volume":"14","author":[{"given":"Marco","family":"Silvano","sequence":"first","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"given":"Ricardo","family":"Correia","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5295-8822","authenticated-orcid":false,"given":"Nikolaus","family":"Virgolini","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2817-9527","authenticated-orcid":false,"given":"Colin","family":"Clarke","sequence":"additional","affiliation":[{"name":"NIBRT, National Institute for Bioprocessing Research and Training, Fosters Avenue, Blackrock, Co., A94 X099 Dublin, Ireland"},{"name":"School of Chemical and Bioprocess Engineering, University College Dublin, D04 V1W8 Dublin, Ireland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1445-3556","authenticated-orcid":false,"given":"Paula M.","family":"Alves","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0237-5805","authenticated-orcid":false,"given":"In\u00eas A.","family":"Isidro","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0414-4899","authenticated-orcid":false,"given":"Ant\u00f3nio","family":"Rold\u00e3o","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1099\/vir.0.067108-0","article-title":"Thirty years of baculovirus\u2013insect cell protein expression: From dark horse to mainstream technology","volume":"96","author":"Pijlman","year":"2015","journal-title":"J. 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