title: Changes in the Length of the Neuraminidase Stalk Region Impact H7N9 Virulence in Mice.
abstract: The neuraminidase stalk of the newly emerged H7N9 influenza virus possesses a 5-amino-acid deletion. This study focuses on characterizing the biological functions of H7N9 with varied neuraminidase stalk lengths. Results indicate that the 5-amino-acid deletion had no impact on virus infectivity or replication in vitro or in vivo compared to that of a virus with a full-length stalk, but enhanced virulence in mice was observed for H7N9 encoding a 19- to 20-amino-acid deletion, suggesting that N9 stalk length impacts virulence in mammals, as N1 stalk length does.
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third People's Hospital, Shenzhen, China Center for Influenza Research and Early Warning (CASCIRE), Chinese Academy of Sciences, Beijing, China beeyh@im.ac.cn gaof@im.ac.cn.
authors.forename: Yuhai
authors.initials: Y
authors.lastname: Bi
authors.affiliation: Laboratory of Protein Engineering and Vaccines, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China Center for Influenza Research and Early Warning (CASCIRE), Chinese Academy of Sciences, Beijing, China.
authors.forename: Haixia
authors.initials: H
authors.lastname: Xiao
authors.affiliation: CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Hubei, China Center for Influenza Research and Early Warning (CASCIRE), Chinese Academy of Sciences, Beijing, China.
authors.forename: Quanjiao
authors.initials: Q
authors.lastname: Chen
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Lifeng
authors.initials: L
authors.lastname: Fu
authors.affiliation: National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
authors.forename: Chuansong
authors.initials: C
authors.lastname: Quan
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Gary
authors.initials: G
authors.lastname: Wong
authors.affiliation: Center for Influenza Research and Early Warning (CASCIRE), Chinese Academy of Sciences, Beijing, China National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Joel
authors.initials: J
authors.lastname: Haywood
authors.affiliation: Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third People's Hospital, Shenzhen, China.
authors.forename: Yingxia
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third People's Hospital, Shenzhen, China.
authors.forename: Boping
authors.initials: B
authors.lastname: Zhou
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yan
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China Center for Influenza Research and Early Warning (CASCIRE), Chinese Academy of Sciences, Beijing, China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Liu
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third People's Hospital, Shenzhen, China Laboratory of Protein Engineering and Vaccines, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China Center for Influenza Research and Early Warning (CASCIRE), Chinese Academy of Sciences, Beijing, China National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Beijing, China Collaborative Innovation Center for Diagnosis and Treatment of Infectious Disease, Zhejiang University, Hanzhou, China Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China beeyh@im.ac.cn gaof@im.ac.cn.
authors.forename: George F
authors.initials: GF
authors.lastname: Gao
mesh_terms: D000818:Animals; D001835:Body Weight; D016207:Cytokines / Q000032:analysis; D006651:Histocytochemistry; D064766:Influenza A Virus, H7N9 Subtype / Q000235:genetics* / Q000472:pathogenicity*; D008168:Lung / Q000473:pathology / Q000821:virology; D008807:Mice, Inbred BALB C; D009439:Neuraminidase / Q000235:genetics*; D009976:Orthomyxoviridae Infections / Q000473:pathology / Q000821:virology*; D017384:Sequence Deletion; D019562:Viral Load; D014764:Viral Proteins / Q000235:genetics*; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D016207:Cytokines; D014764:Viral Proteins; D037521:Virulence Factors; C487630:NA protein, influenza A virus; D009439:Neuraminidase