title: The nucleoprotein and matrix protein segments of H5N1 influenza viruses are responsible for dominance in embryonated eggs.
abstract: Since their emergence in 1996 in southern China, highly pathogenic H5N1 avian influenza viruses have spread widely and continue to circulate in some countries. Genetic reassortment has created multiple H5N1 virus lineages, some of which are dominant in nature. However, the mechanism by which certain H5N1 influenza virus lineages (or genotypes) become dominant in avian species remains unknown. Here, we used competitive inoculation and genetic analysis of the resultant viruses to show that the nucleoprotein (NP) and matrix protein (M) segments of Fujian-like viruses (clade 2.3.4), which became predominant in southern China in mid-2006, are responsible for viral dominance in embryonated eggs. We further found that specific residues in the NP and M proteins play key roles in conferring this viral dominance; specifically, a glutamic acid at position 66 in M2 was conserved among the Fujian-like viruses. These results suggest roles for these viral proteins in influenza virus dominance.
authors.affiliation: Department of Microbiology, Hokkaido University Graduate School of Medicine, Hokkaido, Japan.|Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Shimizu
authors.affiliation: Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Chengjun
authors.initials: C
authors.lastname: Li
authors.affiliation: Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Muramoto
authors.affiliation: Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Yamada
authors.affiliation: Department of Microbiology, Hokkaido University Graduate School of Medicine, Hokkaido, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Arikawa
authors.affiliation: Animal Influenza Laboratory of the Ministry of Agriculture and National Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China.
authors.forename: Hualan
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA.|ERATO Infection-Induced Host Responses Project, Japan Science and Technology Agency, Saitama, Japan.|Division of Zoonosis, Department of Microbiology and Infectious Diseases, Graduate School of Medicine, Kobe University, Hyogo, Japan.|Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.|International Research Center for Infectious Diseases, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kawaoka
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001717:Birds; D002642:Chick Embryo; D053124:Influenza A Virus, H5N1 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D005585:Influenza in Birds / Q000821:virology*; D008969:Molecular Sequence Data; D009698:Nucleoproteins / Q000235:genetics / Q000378:metabolism*; D014763:Viral Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D017735:Virus Latency
chemical_list: C488936:M1 protein, Influenza A virus; D009698:Nucleoproteins; D014763:Viral Matrix Proteins