title: Role of stem glycans attached to haemagglutinin in the biological characteristics of H5N1 avian influenza virus.
abstract: There are three conserved N-linked glycosites, namely, Asn10, Asn23 and Asn286, in the stem region of haemagglutinin (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 cells in comparison with that of the 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 in HA cleavage, replication, thermostability, pH stability, and antigenicity of H5N1 AIVs.
authors: College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Research Centre of Engineering and Technology for the Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Co-Innovation Centre for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, 225009, PR China.
authors: Xiaojian
authors: X
authors: Zhang
authors: Jiangsu Research Centre of Engineering and Technology for the Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Co-Innovation Centre for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, 225009, PR China.|College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China.
authors: Sujuan
authors: S
authors: Chen
authors: Jiangsu Research Centre of Engineering and Technology for the Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Co-Innovation Centre for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, 225009, PR China.|College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China.
authors: Da
authors: D
authors: Yang
authors: Jiangsu Research Centre of Engineering and Technology for the Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Co-Innovation Centre for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, 225009, PR China.|College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China.
authors: Xiao
authors: X
authors: Wang
authors: Jiangsu Research Centre of Engineering and Technology for the Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Co-Innovation Centre for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, 225009, PR China.|College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China.
authors: Jingjing
authors: J
authors: Zhu
authors: Jiangsu Research Centre of Engineering and Technology for the Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Co-Innovation Centre for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, 225009, PR China.|College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China.
authors: Daxin
authors: D
authors: Peng
authors: Jiangsu Research Centre of Engineering and Technology for the Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, 225009, PR China.|Jiangsu Co-Innovation Centre for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, 225009, PR China.|College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China.
authors: Xiufan
authors: X
authors: Liu
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D002460:Cell Line; D002645:Chickens; D004252:DNA Mutational Analysis; D004285:Dogs; D006031:Glycosylation; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000737:chemistry* / Q000502:physiology*; D016297:Mutagenesis, Site-Directed; D011134:Polysaccharides / Q000032:analysis*; D011499:Protein Processing, Post-Translational; D014779:Virus Replication
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; D011134:Polysaccharides; C109963:hemagglutinin, avian influenza A virus