[{"command":"settings","settings":{"pluralDelimiter":"\u0003","suppressDeprecationErrors":true,"entitySetting":{"type":"bibcite_reference","bundle":"journal_article","mapping":{"node":{"blog":"blog","class":"classes","events":"calendar","faq":"faq","link":"links","news":"news","page":"","person":"people","presentation":"presentations","software_project":"software","software_release":"software"},"bibcite_reference":{"*":"publications"},"paragraph":{"class_material":"classes"}},"viewmode":"teaser"},"user":{"uid":0,"permissionsHash":"7f1a171f8b0b5a764cab6d1b118f6329cfc3469f3145adbaf7b7495bbf60a5ea"}},"merge":true},{"command":"add_js","selector":"body","data":[{"src":"\/files\/js\/js_DOoUrEhS-bkVvWBnZGMbXVBHnh5Ov7QOD3C6k4k3980.js?scope=footer\u0026delta=0\u0026language=en\u0026theme=texasbio_eligendi\u0026include=eJzLL44vKE3KyUxOLMnMzyvWTykqLUjM0ctHFdbLzSxO1ikrzixJ1U_OzytJrSgpTcxxK83JCctMLQcAsjEbVw"}]},{"command":"insert","method":"replaceWith","selector":"#","data":"\n  \u003Cdiv class=\u0022field field--name-field-widget-title field--type-string field--label-visually_hidden field--mode-full\u0022\u003E\n    \u003Cdiv class=\u0022field--label sr-only\u0022\u003EWidget Title\u003C\/div\u003E\n              \u003Cdiv class=\u0022field--item\u0022\u003EMolecular mechanisms of influenza viral pathogenesis\u003C\/div\u003E\n          \u003C\/div\u003E\n\n\u003Cul  id=\u0022list-of-posts\u0022 more_link_id=\u0022node-readmore\u0022 class=\u0022publications view-teaser grid-view\u0022\u003E\n \u003Cli\u003E\n\u003Carticle class=\u0022bibcite-reference bibcite bibcite--teaser\u0022\u003E\n  \n  \n  \n\n  \u003Cdiv class=\u0022bibcite__content\u0022\u003E\n    \u003Cdiv class=\u0022bibcite-citation\u0022\u003E\n      \u003Cdiv class=\u0022csl-bib-body\u0022\u003E\u003Cdiv class=\u0022csl-entry\u0022\u003ENogales, Aitor, John Steel, Wen-Chun Liu, Anice C Lowen, Laura Rodriguez, Kevin Chiem, Andrew Cox, et al. (2022) 2022. \u201c\u003Ca href=\u0022\/lms-lab\/publications\/mutation-l319q-pb1-polymerase-subunit-improves-attenuation-candidate-live-attenuated\u0022 hreflang=\u0022en\u0022\u003EMutation L319Q in the PB1 Polymerase Subunit Improves Attenuation of a Candidate Live-Attenuated Influenza A Virus Vaccine.\u003C\/a\u003E\u201d. \u003Ci\u003EMicrobiology Spectrum\u003C\/i\u003E 10 (3): e0007822. https:\/\/doi.org\/10.1128\/spectrum.00078-22.\u003C\/div\u003E\u003C\/div\u003E\n  \u003C\/div\u003E\n\n  \u003Cdiv class=\u0022field field--name-publishers-version field--type-link field--label-visually_hidden field--mode-teaser\u0022\u003E\n    \u003Cdiv class=\u0022field--label sr-only\u0022\u003EPublisher\u0027s Version\u003C\/div\u003E\n              \u003Cdiv class=\u0022field--item\u0022\u003E\u003Ca href=\u0022https:\/\/www.ncbi.nlm.nih.gov\/pubmed\/35583364\u0022\u003EPublisher\u0026#039;s Version\u003C\/a\u003E\u003C\/div\u003E\n          \u003C\/div\u003E\n                \u003Cdiv class=\u0022field--label field--abstract\u0022\u003E\n      \u003Cbutton class=\u0022btn-abstract collapsed\u0022 data-toggle=\u0022collapse\u0022 data-target=\u0022#collapseAbstract\u0022 aria-expanded=\u0022false\u0022 aria-controls=\u0022collapseAbstract\u0022\u003EAbstract \u003C\/button\u003E\n    \u003C\/div\u003E\n                  \u003Cdiv class=\u0022field--item abstract--content collapse\u0022 id=\u0022collapseAbstract\u0022 aria-expanded=\u0026quot;false\u0026quot;\u003E\u003Cp\u003EInfluenza A viruses (IAV) remain emerging threats to human public health. Live-attenuated influenza vaccines (LAIV) are one of the most effective prophylactic options to prevent disease caused by influenza infections. However, licensed LAIV remain restricted for use in 2- to 49-year-old healthy and nonpregnant people. Therefore, development of LAIV with increased safety, immunogenicity, and protective efficacy is highly desired. The U.S.-licensed LAIV is based on the master donor virus (MDV) A\/Ann Arbor\/6\/60 H2N2 backbone, which was generated by adaptation of the virus to growth at low temperatures. Introducing the genetic signature of the U.S. MDV into the backbone of other IAV strains resulted in varying levels of attenuation. While the U.S. MDV mutations conferred an attenuated phenotype to other IAV strains, the same amino acid changes did not significantly attenuate the pandemic A\/California\/04\/09 H1N1 (pH1N1) strain. To attenuate pH1N1, we replaced the conserved leucine at position 319 with glutamine (L319Q) in PB1 and analyzed the \u003Ci\u003Ein vitro\u003C\/i\u003E and \u003Ci\u003Ein vivo\u003C\/i\u003E properties of pH1N1 viruses containing either PB1 L319Q alone or in combination with the U.S. MDV mutations using two animal models of influenza infection and transmission, ferrets and guinea pigs. Our results demonstrated that L319Q substitution in the pH1N1 PB1 alone or in combination with the mutations of the U.S. MDV resulted in reduced pathogenicity (ferrets) and transmission (guinea pigs), and an enhanced temperature sensitive phenotype. These results demonstrate the feasibility of generating an attenuated MDV based on the backbone of a contemporary pH1N1 IAV strain. IMPORTANCE Vaccination represents the most effective strategy to reduce the impact of seasonal IAV infections. Although LAIV are superior in inducing protection and sterilizing immunity, they are not recommended for many individuals who are at high risk for severe disease. Thus, development of safer and more effective LAIV are needed. A concern with the current MDV used to generate the U.S.-licensed LAIV is that it is based on a virus isolated in 1960. Moreover, mutations that confer the temperature-sensitive, cold-adapted, and attenuated phenotype of the U.S. MDV resulted in low level of attenuation in the contemporary pandemic A\/California\/04\/09 H1N1 (pH1N1). Here, we show that introduction of PB1 L319Q substitution, alone or in combination with the U.S. MDV mutations, resulted in pH1N1 attenuation. These findings support the development of a novel LAIV MDV based on a contemporary pH1N1 strain as a medical countermeasure against currently circulating H1N1 IAV.\u003C\/p\u003E\n\u003C\/div\u003E\n        \n  \u003C\/div\u003E\n\u003C\/article\u003E\n\u003C\/li\u003E\n \u003Cli\u003E\n\u003Carticle class=\u0022bibcite-reference bibcite bibcite--teaser\u0022\u003E\n  \n  \n  \n\n  \u003Cdiv class=\u0022bibcite__content\u0022\u003E\n    \u003Cdiv class=\u0022bibcite-citation\u0022\u003E\n      \u003Cdiv class=\u0022csl-bib-body\u0022\u003E\u003Cdiv class=\u0022csl-entry\u0022\u003EDeDiego, Marta L, Aitor Nogales, Kris Lambert-Emo, Luis Martinez-Sobrido, and David J Topham. (2016) 2016. \u201c\u003Ca href=\u0022\/lms-lab\/publications\/ns1-protein-mutation-i64t-affects-interferon-responses-and-virulence-circulating-h3n2\u0022 hreflang=\u0022en\u0022\u003ENS1 Protein Mutation I64T Affects Interferon Responses and Virulence of Circulating H3N2 Human Influenza A Viruses.\u003C\/a\u003E\u201d. \u003Ci\u003EJournal of Virology\u003C\/i\u003E 90 (21): 9693-9711. https:\/\/doi.org\/10.1128\/JVI.01039-16.\u003C\/div\u003E\u003C\/div\u003E\n  \u003C\/div\u003E\n\n  \u003Cdiv class=\u0022field field--name-publishers-version field--type-link field--label-visually_hidden field--mode-teaser\u0022\u003E\n    \u003Cdiv class=\u0022field--label sr-only\u0022\u003EPublisher\u0027s Version\u003C\/div\u003E\n              \u003Cdiv class=\u0022field--item\u0022\u003E\u003Ca href=\u0022https:\/\/www.ncbi.nlm.nih.gov\/pubmed\/27535054\u0022\u003EPublisher\u0026#039;s Version\u003C\/a\u003E\u003C\/div\u003E\n          \u003C\/div\u003E\n                \u003Cdiv class=\u0022field--label field--abstract\u0022\u003E\n      \u003Cbutton class=\u0022btn-abstract collapsed\u0022 data-toggle=\u0022collapse\u0022 data-target=\u0022#collapseAbstract\u0022 aria-expanded=\u0022false\u0022 aria-controls=\u0022collapseAbstract\u0022\u003EAbstract \u003C\/button\u003E\n    \u003C\/div\u003E\n                  \u003Cdiv class=\u0022field--item abstract--content collapse\u0022 id=\u0022collapseAbstract\u0022 aria-expanded=\u0026quot;false\u0026quot;\u003E\u003Cp\u003E\u003Cb\u003EUNLABELLED: \u003C\/b\u003EInfluenza NS1 protein is the main viral protein counteracting host innate immune responses, allowing the virus to efficiently replicate in interferon (IFN)-competent systems. In this study, we analyzed NS1 protein variability within influenza A (IAV) H3N2 viruses infecting humans during the 2012-2013 season. We also evaluated the impact of the mutations on the ability of NS1 proteins to inhibit host innate immune responses and general gene expression. Surprisingly, a previously unidentified mutation in the double-stranded RNA (dsRNA)-binding domain (I64T) decreased NS1-mediated general inhibition of host protein synthesis by decreasing its interaction with cleavage and polyadenylation specificity factor 30 (CPSF30), leading to increased innate immune responses after viral infection. Notably, a recombinant A\/Puerto Rico\/8\/34 H1N1 virus encoding the H3N2 NS1-T64 protein was highly attenuated in mice, most likely because of its ability to induce higher antiviral IFN responses at early times after infection and because this virus is highly sensitive to the IFN-induced antiviral state. Interestingly, using peripheral blood mononuclear cells (PBMCs) collected at the acute visit (2 to 3 days after infection), we show that the subject infected with the NS1-T64 attenuated virus has diminished responses to interferon and to interferon induction, suggesting why this subject could be infected with this highly IFN-sensitive virus. These data demonstrate the importance of influenza virus surveillance in identifying new mutations in the NS1 protein, affecting its ability to inhibit innate immune responses and, as a consequence, the pathogenicity of the virus.\u003C\/p\u003E\n\n\u003Cp\u003E\u003Cb\u003EIMPORTANCE: \u003C\/b\u003EInfluenza A and B viruses are one of the most common causes of respiratory infections in humans, causing 1 billion infections and between 300,000 and 500,000 deaths annually. Influenza virus surveillance to identify new mutations in the NS1 protein affecting innate immune responses and, as a consequence, the pathogenicity of the circulating viruses is highly relevant. Here, we analyzed amino acid variability in the NS1 proteins from human seasonal viruses and the effect of the mutations in innate immune responses and virus pathogenesis. A previously unidentified mutation in the dsRNA-binding domain decreased NS1-mediated general inhibition of host protein synthesis and the interaction of the protein with CPSF30. This mutation led to increased innate immune responses after viral infection, augmented IFN sensitivity, and virus attenuation in mice. Interestingly, using PBMCs, the subject infected with the virus encoding the attenuating mutation induced decreased antiviral responses, suggesting why this subject could be infected with this virus.\u003C\/p\u003E\n\u003C\/div\u003E\n        \n  \u003C\/div\u003E\n\u003C\/article\u003E\n\u003C\/li\u003E\n \u003Cli\u003E\n\u003Carticle class=\u0022bibcite-reference bibcite bibcite--teaser\u0022\u003E\n  \n  \n  \n\n  \u003Cdiv class=\u0022bibcite__content\u0022\u003E\n    \u003Cdiv class=\u0022bibcite-citation\u0022\u003E\n      \u003Cdiv class=\u0022csl-bib-body\u0022\u003E\u003Cdiv class=\u0022csl-entry\u0022\u003ENogales, Aitor, Luis Martinez-Sobrido, David J Topham, and Marta L DeDiego. (2017) 2017. \u201c\u003Ca href=\u0022\/lms-lab\/publications\/ns1-protein-amino-acid-changes-d189n-and-v194i-affect-interferon-responses\u0022 hreflang=\u0022en\u0022\u003ENS1 Protein Amino Acid Changes D189N and V194I Affect Interferon Responses, Thermosensitivity, and Virulence of Circulating H3N2 Human Influenza A Viruses.\u003C\/a\u003E\u201d. \u003Ci\u003EJournal of Virology\u003C\/i\u003E 91 (5). https:\/\/doi.org\/10.1128\/JVI.01930-16.\u003C\/div\u003E\u003C\/div\u003E\n  \u003C\/div\u003E\n\n  \u003Cdiv class=\u0022field field--name-publishers-version field--type-link field--label-visually_hidden field--mode-teaser\u0022\u003E\n    \u003Cdiv class=\u0022field--label sr-only\u0022\u003EPublisher\u0027s Version\u003C\/div\u003E\n              \u003Cdiv class=\u0022field--item\u0022\u003E\u003Ca href=\u0022https:\/\/www.ncbi.nlm.nih.gov\/pubmed\/28003482\u0022\u003EPublisher\u0026#039;s Version\u003C\/a\u003E\u003C\/div\u003E\n          \u003C\/div\u003E\n                \u003Cdiv class=\u0022field--label field--abstract\u0022\u003E\n      \u003Cbutton class=\u0022btn-abstract collapsed\u0022 data-toggle=\u0022collapse\u0022 data-target=\u0022#collapseAbstract\u0022 aria-expanded=\u0022false\u0022 aria-controls=\u0022collapseAbstract\u0022\u003EAbstract \u003C\/button\u003E\n    \u003C\/div\u003E\n                  \u003Cdiv class=\u0022field--item abstract--content collapse\u0022 id=\u0022collapseAbstract\u0022 aria-expanded=\u0026quot;false\u0026quot;\u003E\u003Cp\u003EInfluenza virus NS1 protein is a nonstructural, multifunctional protein that counteracts host innate immune responses, modulating virus pathogenesis. NS1 protein variability in subjects infected with H3N2 influenza A viruses (IAVs) during the 2010\/2011 season was analyzed, and amino acid changes in residues 86, 189, and 194 were found. The consequences of these mutations for the NS1-mediated inhibition of IFN responses and the pathogenesis of the virus were evaluated, showing that NS1 mutations D189N and V194I impaired the ability of the NS1 protein to inhibit general gene expression, most probably because these mutations decreased the binding of NS1 to the cleavage and polyadenylation specificity factor 30 (CPSF30). A recombinant A\/Puerto Rico\/8\/34 (PR8) H1N1 virus encoding the H3N2 NS1-D189N protein was slightly attenuated, whereas the virus encoding the H3N2 NS1-V194I protein was further attenuated in mice. The higher attenuation of this virus could not be explained by differences in the ability of the two NS1 proteins to counteract host innate immune responses, indicating that another factor must be responsible. In fact, we showed that the virus encoding the H3N2 NS1-V194I protein demonstrated a temperature-sensitive (ts) phenotype, providing a most likely explanation for the stronger attenuation observed. As far as we know, this is the first description of a mutation in NS1 residue 194 conferring a ts phenotype. These studies are relevant in order to identify new residues important for NS1 functions and in human influenza virus surveillance to assess mutations affecting the pathogenicity of circulating viruses.IMPORTANCE Influenza viral infections represent a serious public health problem, with influenza virus causing a contagious respiratory disease that is most effectively prevented through vaccination. The multifunctional nonstructural protein 1 (NS1) is the main viral factor counteracting the host antiviral response. Therefore, influenza virus surveillance to identify new mutations in the NS1 protein affecting the pathogenicity of the circulating viruses is highly important. In this work, we evaluated amino acid variability in the NS1 proteins from H3N2 human seasonal viruses and the effect of the mutations on innate immune responses and virus pathogenesis. NS1 mutations D189N and V194I impaired the ability of the NS1 protein to inhibit general gene expression, and recombinant viruses harboring these mutations were attenuated in a mouse model of influenza infection. Interestingly, a virus encoding the H3N2 NS1-V194I protein demonstrated a temperature-sensitive phenotype, further attenuating the virus \u003Ci\u003Ein vivo\u003C\/i\u003E.\u003C\/p\u003E\n\u003C\/div\u003E\n        \n  \u003C\/div\u003E\n\u003C\/article\u003E\n\u003C\/li\u003E\n\u003C\/ul\u003E\n  \u003Cnav role=\u0022navigation\u0022 aria-labelledby=\u0022pagination-for-influenza-molecular-mechanisms-of-influenza-viral-pathogenesis-publications-lop\u0022 id=pager-heading\u003E\n    \u003Ch3 id=\u0022pagination-for-influenza-molecular-mechanisms-of-influenza-viral-pathogenesis-publications-lop\u0022 class=\u0022visually-hidden\u0022\u003Epagination for influenza molecular mechanisms of influenza viral pathogenesis publications lop\u003C\/h3\u003E\n    \u003Cul class=\u0022js-pager__items pager-mini\u0022\u003E\n            \u003Cli class=\u0022current\u0022\u003E\n        \u003Cspan aria-live=\u0022polite\u0022\u003E\n            \u003Cspan class=\u0022visually-hidden\u0022\u003EInfluenza - Molecular mechanisms of influenza viral pathogenesis Publications LOP\u003C\/span\u003E\n            1 of 4\n          \u003C\/span\u003E      \u003C\/li\u003E\n              \u003Cli\u003E\n          \u003Ca href=\u0022\/lms-lab\/refresh-widget-content\/2934?page=1\u0026amp;selector=list-of-posts\u0026amp;pagerid=pager-heading\u0026amp;moreid=node-readmore\u0022 class=\u0022use-ajax next\u0022 rel=\u0022next\u0022\u003E\u003Cspan aria-hidden=\u0022true\u0022\u003E\u203a\u203a\u003C\/span\u003E\u003Cspan class=\u0022visually-hidden\u0022\u003ENext page\u003C\/span\u003E\u003C\/a\u003E\n        \u003C\/li\u003E\n          \u003C\/ul\u003E\n  \u003C\/nav\u003E\n\n\u003Cdiv class=\u0022node-readmore\u0022 id=node-readmore\u003E\u003C\/div\u003E\n","settings":null},{"command":"insert","method":"replaceWith","selector":"#","data":"","settings":null},{"command":"insert","method":"replaceWith","selector":"#","data":"","settings":null},{"command":"insert","method":"replaceWith","selector":".field--name-field-widget-title","data":"","settings":null}]