title: A PB1 T296R substitution enhance polymerase activity and confer a virulent phenotype to a 2009 pandemic H1N1 influenza virus in mice.
abstract: While the 2009 pandemic H1N1 virus has become established in the human population as a seasonal influenza virus, continued adaptation may alter viral virulence. Here, we passaged a 2009 pandemic H1N1 virus (A/Changchun/01/2009) in mice. Serial passage in mice generated viral variants with increased virulence. Adapted variants displayed enhanced replication kinetics in vitro and vivo. Analysis of the variants genomes revealed 6 amino acid changes in the PB1 (T296R), PA (I94V), HA (H3 numbering; N159D, D225G, and R226Q), and NP (D375N). Using reverse genetics, we found that a PB1-T296R substitution found in all adapted viral variants enhanced viral replication kinetics in vitro and vivo, increased viral polymerase activity in human cells, and was sufficient for enhanced virulence of the 2009 pandemic H1N1 virus in mice. Therefore, we defined a novel influenza pathogenic determinant, providing further insights into the pathogenesis of influenza viruses in mammals.
authors.affiliation: Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China; Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Dairy Cattle Research Center, Shandong Academy of Agricultural Sciences, Jinan 250132, China.
authors.forename: Kaihui
authors.initials: K
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Weiyang
authors.initials: W
authors.lastname: Sun
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Xinghai
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Yuanguo
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Tiecheng
authors.initials: T
authors.lastname: Wang
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Hualei
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
authors.forename: Qianyi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Xin
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Li
authors.initials: L
authors.lastname: Xue
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China.
authors.forename: Songtao
authors.initials: S
authors.lastname: Yang
authors.affiliation: Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Qin
authors.affiliation: Department of Microbiology, University of Wisconsin-La Crosse, La Crosse, Wisconsin, 54601, USA.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Wilker
authors.affiliation: Basic Medical College,Changchun University of Traditional Chinese Medicine, Changchun, 130117, China.
authors.forename: Donghui
authors.initials: D
authors.lastname: Yue
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
authors.forename: Hualan
authors.initials: H
authors.lastname: Chen
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China. Electronic address: gaoyuwei@gmail.com.
authors.forename: Yuwei
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China; Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China; Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, 130122, China. Electronic address: xiaxianzhu1939@126.com.
authors.forename: Xianzhu
authors.initials: X
authors.lastname: Xia
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D007251:Influenza, Human / Q000453:epidemiology / Q000821:virology*; D051379:Mice; D008807:Mice, Inbred BALB C; D020125:Mutation, Missense; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism*; D014774:Virulence
chemical_list: D014764:Viral Proteins; C077346:influenza virus polymerase basic protein 1
keywords: H1N1; Influenza A virus; Mouse model; Virulence