tetano
Editor, Senior Moderator
J Gen Virol. 2015 Feb 9. pii: vir.0.000082. doi: 10.1099/vir.0.000082. [Epub ahead of print]
[h=1]Role of Stem Glycans Attached to Haemagglutinin on the Biological Characteristics of H5N1 Avian Influenza Virus.[/h] Zhang X[SUP]1[/SUP], Chen S[SUP]1[/SUP], Yang D[SUP]1[/SUP], Wang X[SUP]1[/SUP], Zhu J[SUP]1[/SUP], Peng D[SUP]1[/SUP], Liu X[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] There are three conserved N-linked glycosites, namely, Asn10, Asn23, and Asn286, at the stem region of hemagglutinin (HA) in H5N1 avian influenza viruses (AIVs). To understand the effect of glycosylation in the stem domain of HA on the biological characteristics of H5N1 AIVs, we used site-directed mutagenesis to generate different patterns of stem glycans on the HA of A/Mallard/Huadong/S/2005. The results indicated that these three N-glycans were dispensable for the generation of replication-competent influenza viruses. However, when N-glycans at Asn10 plus either Asn23 or Asn268 were removed, the cleavability of HA was almost completely blocked, leading to a significant decrease of the growth rates of the mutant viruses in MDCK and CEF in comparison with that of the wild-type (WT) virus. Moreover, the mutant viruses lacking these oligosaccharides, particularly the N-glycan at Asn10, revealed a significant decrease in thermostability and pH stability compared with the WT virus. Interestingly, the mutant viruses induced a lower level of neutralizing antibodies against the WT virus, and most of the mutant viruses were more sensitive to neutralizing antibodies than the WT virus. Taken together, these data strongly suggest that the HA stem glycans play a critical role on HA cleavage, replication, thermostability, pH stability, and antigenicity of H5N1 AIVs.
PMID: 25667326 [PubMed - as supplied by publisher]
[h=1]Role of Stem Glycans Attached to Haemagglutinin on the Biological Characteristics of H5N1 Avian Influenza Virus.[/h] Zhang X[SUP]1[/SUP], Chen S[SUP]1[/SUP], Yang D[SUP]1[/SUP], Wang X[SUP]1[/SUP], Zhu J[SUP]1[/SUP], Peng D[SUP]1[/SUP], Liu X[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] There are three conserved N-linked glycosites, namely, Asn10, Asn23, and Asn286, at the stem region of hemagglutinin (HA) in H5N1 avian influenza viruses (AIVs). To understand the effect of glycosylation in the stem domain of HA on the biological characteristics of H5N1 AIVs, we used site-directed mutagenesis to generate different patterns of stem glycans on the HA of A/Mallard/Huadong/S/2005. The results indicated that these three N-glycans were dispensable for the generation of replication-competent influenza viruses. However, when N-glycans at Asn10 plus either Asn23 or Asn268 were removed, the cleavability of HA was almost completely blocked, leading to a significant decrease of the growth rates of the mutant viruses in MDCK and CEF in comparison with that of the wild-type (WT) virus. Moreover, the mutant viruses lacking these oligosaccharides, particularly the N-glycan at Asn10, revealed a significant decrease in thermostability and pH stability compared with the WT virus. Interestingly, the mutant viruses induced a lower level of neutralizing antibodies against the WT virus, and most of the mutant viruses were more sensitive to neutralizing antibodies than the WT virus. Taken together, these data strongly suggest that the HA stem glycans play a critical role on HA cleavage, replication, thermostability, pH stability, and antigenicity of H5N1 AIVs.
PMID: 25667326 [PubMed - as supplied by publisher]