{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T23:15:58Z","timestamp":1789514158697,"version":"build-2803163510"},"reference-count":108,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p>Influenza A virus (IAV) is a zoonotic pathogen with a broad host range, posing an ongoing threat to global public health. As the core subunit of the IAV polymerase, polymerase basic protein 1 (PB1) is essential for viral replication and transcription, and its mutations are key drivers of viral evolution. This review evaluates the impact of PB1 mutations on IAV evolution, with a focus on polymerase activity, host adaptation, transmissibility, and virulence. Additionally, it discusses the implications of these mutations for vaccine development. The review aims to provide insights that can inform influenza surveillance, identify novel antiviral targets, and guide vaccine design.<\/jats:p>","DOI":"10.3389\/fmicb.2026.1768665","type":"journal-article","created":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T06:42:42Z","timestamp":1769668962000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":3,"title":["PB1 mutations as key drivers of influenza A virus evolution"],"prefix":"10.3389","volume":"17","author":[{"given":"Canxin","family":"Fang","sequence":"first","affiliation":[{"name":"Key Laboratory of Infectious Diseases and Biosafety, Education Department of Guizhou Province","place":["Zunyi, China"]},{"name":"Department of Microbiology, School of Preclinical Medicine, Zunyi Medical University","place":["Zunyi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Microbiology, School of Preclinical Medicine, Zunyi Medical University","place":["Zunyi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yutong","family":"Feng","sequence":"additional","affiliation":[{"name":"Key Laboratory of Infectious Diseases and Biosafety, Education Department of Guizhou Province","place":["Zunyi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Microbiology, School of Preclinical Medicine, Zunyi Medical University","place":["Zunyi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shengyu","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Infectious Diseases and Biosafety, Education Department of Guizhou Province","place":["Zunyi, China"]},{"name":"Department of Microbiology, School of Preclinical Medicine, Zunyi Medical University","place":["Zunyi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,29]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"395","DOI":"10.3390\/vaccines10030395","article-title":"Understanding the variability of certain biological properties of H1N1pdm09 influenza viruses","volume":"10","author":"Al Farroukh","year":"2022","journal-title":"Vaccine"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"198795","DOI":"10.1016\/j.virusres.2022.198795","article-title":"Optimization of a(H1N1)pdm09 vaccine seed viruses: the source of PB1 and HA vRNA as a major determinant for antigen yield","volume":"315","author":"Almeida","year":"2022","journal-title":"Virus Res."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"e1005583","DOI":"10.1371\/journal.ppat.1005583","article-title":"Novel polymerase gene mutations for human adaptation in clinical isolates of avian H5N1 influenza viruses","volume":"12","author":"Arai","year":"2016","journal-title":"PLoS Pathog."},{"key":"ref4","doi-asserted-by":"publisher","first-page":"2332652","DOI":"10.1080\/22221751.2024.2332652","article-title":"Amino acids in the polymerase complex of shorebird-isolated H1N1 influenza virus impact replication and host-virus interactions in mammalian models","volume":"13","author":"Bai","year":"2024","journal-title":"Emerg Microbes Infect."},{"key":"ref5","doi-asserted-by":"publisher","first-page":"3741","DOI":"10.1128\/jvi.02346-12","article-title":"T-705 (favipiravir) induces lethal mutagenesis in influenza A H1N1 viruses in vitro","volume":"87","author":"Baranovich","year":"2013","journal-title":"J. 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