Influenza A virus (A/Hong Kong/1073/99(H9N2))



Top Publications

  1. Wang S, Shi W, Mweene A, Wei H, Bai G, Liu J. Genetic analysis of the nonstructural (NS) genes of H9N2 chicken influenza viruses isolated in China during 1998-2002. Virus Genes. 2005;31:329-35 pubmed publisher
  2. Lin Y, Shaw M, Gregory V, Cameron K, Lim W, Klimov A, et al. Avian-to-human transmission of H9N2 subtype influenza A viruses: relationship between H9N2 and H5N1 human isolates. Proc Natl Acad Sci U S A. 2000;97:9654-8 pubmed
    ..This common feature emphasizes the apparent propensity of avian viruses with this genetic complement to infect humans and highlights the potential for the emergence of a novel human pathogen. ..
  3. Wan H, Perez D. Amino acid 226 in the hemagglutinin of H9N2 influenza viruses determines cell tropism and replication in human airway epithelial cells. J Virol. 2007;81:5181-91 pubmed
    ..Our results suggest that the variation in residue 226 in the HA affects both cell tropism and replication of H9N2 viruses in HAE cells and may have implications for the abilities of these viruses to infect humans. ..
  4. Qi W, Tian J, Su S, Huang L, Li H, Liao M. Identification of potential virulence determinants associated H9N2 avian influenza virus PB2 E627K mutation by comparative proteomics. Proteomics. 2015;15:1512-24 pubmed publisher
    ..In this study, sp-A as a potential virulence determinant associated H9N2 AIV PB2 E627K mutation was identified using comparative proteomics. ..
  5. Forbes N, Selman M, Pelchat M, Jia J, Stintzi A, Brown E. Identification of adaptive mutations in the influenza A virus non-structural 1 gene that increase cytoplasmic localization and differentially regulate host gene expression. PLoS ONE. 2013;8:e84673 pubmed publisher
    ..To our knowledge this is the first report of roles of adaptive NS1 mutations that impact intracellular localization and regulation of host gene expression. ..
  6. Gao H, Xu G, Sun Y, Qi L, Wang J, Kong W, et al. PA-X is a virulence factor in avian H9N2 influenza virus. J Gen Virol. 2015;96:2587-94 pubmed publisher
  7. Srinivasan K, Raman R, Jayaraman A, Viswanathan K, Sasisekharan R. Quantitative characterization of glycan-receptor binding of H9N2 influenza A virus hemagglutinin. PLoS ONE. 2013;8:e59550 pubmed publisher
    ..Our findings contribute to a framework for monitoring the evolution of H9 HA by understanding effects of molecular changes in HA on glycan receptor-binding properties...
  8. Chen Q, Huang S, Chen J, Zhang S, Chen Z. NA proteins of influenza A viruses H1N1/2009, H5N1, and H9N2 show differential effects on infection initiation, virus release, and cell-cell fusion. PLoS ONE. 2013;8:e54334 pubmed publisher
    ..These phenomena might be partially due to NA proteins' different specificity to ?2-3/2-6-sialylated carbohydrate chains, but the exact mechanism remains to be explored...
  9. Davidson I, Shkoda I, Golender N, Perk S, Lapin K, Khinich Y, et al. Genetic characterization of HA gene of low pathogenic H9N2 influenza viruses isolated in Israel during 2006-2012 periods. Virus Genes. 2013;46:255-63 pubmed publisher

More Information


  1. Wang J, Sun Y, Xu Q, Tan Y, Pu J, Yang H, et al. Mouse-adapted H9N2 influenza A virus PB2 protein M147L and E627K mutations are critical for high virulence. PLoS ONE. 2012;7:e40752 pubmed publisher
    ..Thus, our results show that the combination of PB2 amino acids at position 147 and 627 is critical for the increased pathogenicity of H9N2 influenza virus in mammalian host...
  2. Leonov H, Arkin I. pH-driven helix rotations in the influenza M2 H+ channel: a potential gating mechanism. Eur Biophys J. 2010;39:1043-9 pubmed publisher
    ..Finally, we propose a mechanism for channel gating that involves protonation of the histidine residues that necessities their increased solvation. ..
  3. Jimenez G, Planchon R, Wei Q, Rusalov D, Geall A, Enas J, et al. Vaxfectin-formulated influenza DNA vaccines encoding NP and M2 viral proteins protect mice against lethal viral challenge. Hum Vaccin. 2007;3:157-64 pubmed
    ..Vaxfectin adjuvanticity was confirmed with a low dose of HA pDNA. These promising proof-of-concept data support the clinical development of Vaxfectin-formulated pDNA encoding NP + M2 consensus proteins. ..
  4. Liu J, Shi W, Wu Q, Guo Y. [Sequence analysis of NS1 gene of some H9N2 subtype influenza viruses isolated from chickens in China]. Wei Sheng Wu Xue Bao. 2003;43:547-53 pubmed
  5. Qi X, Zhang H, Wang Q, Wang J. The NS1 protein of avian influenza virus H9N2 induces oxidative-stress-mediated chicken oviduct epithelial cells apoptosis. J Gen Virol. 2016;97:3183-3192 pubmed publisher
    ..Additionally, NS1 protein can induce cellular apoptosis via activating ROS accumulation and mitochondria-mediated apoptotic signalling in COECs. ..
  6. Xu G, Zhang X, Gao W, Wang C, Wang J, Sun H, et al. Prevailing PA Mutation K356R in Avian Influenza H9N2 Virus Increases Mammalian Replication and Pathogenicity. J Virol. 2016;90:8105-14 pubmed publisher
  7. Teng Q, Xu D, Shen W, Liu Q, Rong G, Li X, et al. A Single Mutation at Position 190 in Hemagglutinin Enhances Binding Affinity for Human Type Sialic Acid Receptor and Replication of H9N2 Avian Influenza Virus in Mice. J Virol. 2016;90:9806-9825 pubmed
    ..Our findings suggest that more attention should be given to the H9N2 AIVs with HA-190V during surveillance due to their potential threat to mammals, including humans. ..
  8. James J, Howard W, Iqbal M, Nair V, Barclay W, Shelton H. Influenza A virus PB1-F2 protein prolongs viral shedding in chickens lengthening the transmission window. J Gen Virol. 2016;97:2516-2527 pubmed publisher
    ..We propose that there is a positive pressure to maintain a full-length functional PB1-F2 protein upon infection of avian hosts as it contributes to the effective transmission of IAV in the field. ..
  9. Hussein I, Ma E, Hill N, Meixell B, Lindberg M, Albrecht R, et al. A point mutation in the polymerase protein PB2 allows a reassortant H9N2 influenza isolate of wild-bird origin to replicate in human cells. Infect Genet Evol. 2016;41:279-288 pubmed publisher
    ..However, this effect is not universal, warranting caution in interpreting point mutations without considering protein sequence context. ..
  10. Sediri H, Schwalm F, Gabriel G, Klenk H. Adaptive mutation PB2 D701N promotes nuclear import of influenza vRNPs in mammalian cells. Eur J Cell Biol. 2015;94:368-74 pubmed publisher
    ..These observations suggest that entry of vRNPs into the nucleus depends on controlled interplay of the NLSs of PB2 and NP with the nuclear import machinery. ..
  11. Adel A, Arafa A, Hussein H, El Sanousi A. Molecular and antigenic traits on hemagglutinin gene of avian influenza H9N2 viruses: Evidence of a new escape mutant in Egypt adapted in quails. Res Vet Sci. 2017;112:132-140 pubmed publisher
    ..In conclusion, Egy/G1var is shown to be a new escape mutant variant cluster with an adaptive evolution in quails. ..
  12. Li W, Chen H, Sutton T, Obadan A, Perez D. Interactions between the influenza A virus RNA polymerase components and retinoic acid-inducible gene I. J Virol. 2014;88:10432-47 pubmed publisher
    ..The data suggest that although RIG-I binding by RNA polymerase complex is conserved in different species, it does not appear to play crucial role in the modulation of IFN in vitro...
  13. Tse L, Hamilton A, Friling T, Whittaker G. A novel activation mechanism of avian influenza virus H9N2 by furin. J Virol. 2014;88:1673-83 pubmed publisher
    ..Our data indicate a mechanism for an H9N2 evolutionary pathway that may allow it to gain virulence in a distinct manner from H5 and H7 influenza viruses. ..
  14. Adams S, Xing Z, Li J, Mendoza K, Perez D, Reed K, et al. The effect of avian influenza virus NS1 allele on virus replication and innate gene expression in avian cells. Mol Immunol. 2013;56:358-68 pubmed publisher
    ..Finally, chimeric constructs were used to identify a region of the NS1 gene that conferred the statistically significant differences in expression and replication observed between the alleles...
  15. Li W, Zhang H, Wang G, Zhang C, Zeng X, Liu H, et al. Heterologous interactions between NS1 proteins from different influenza A virus subtypes/strains. Sci China Life Sci. 2012;55:507-15 pubmed publisher
    ..4%-20.9% sequence diversity with NS11, NS51 and NS92. This indicates that the heterologous interactions between NS1 proteins from different influenza A virus subtypes/ strains may be a common event during co-infection. ..
  16. Chockalingam A, Hickman D, Pena L, Ye J, Ferrero A, Echenique J, et al. Deletions in the neuraminidase stalk region of H2N2 and H9N2 avian influenza virus subtypes do not affect postinfluenza secondary bacterial pneumonia. J Virol. 2012;86:3564-73 pubmed publisher
    ..These data suggest that the H2N2 and H9N2 subtypes of avian influenza A viruses can contribute to secondary bacterial pneumonia and deletions in the NA stalk may modulate its outcome in the context of antiviral therapy...
  17. Gohrbandt S, Veits J, Breithaupt A, Hundt J, Teifke J, Stech O, et al. H9 avian influenza reassortant with engineered polybasic cleavage site displays a highly pathogenic phenotype in chicken. J Gen Virol. 2011;92:1843-53 pubmed publisher
    ..23. These results suggest that an HPAIV with a subtype other than H5 or H7 would only emerge under conditions where the HA gene could acquire a polybasic cleavage site and the other viral genes carry additional virulence determinants...
  18. Liu H, Zhang P, Liu X, Liu W, Jia L. [Genetic mutations of heamagglutinin genes of H9N2 subtype influenza A viruses in the field in a five-year period]. Wei Sheng Wu Xue Bao. 2003;43:706-11 pubmed
    ..These findings may be fruitful for making further study of genetic mutations of AIVs in the field and improving the control strategies. ..