Combined insertion of basic and non-basic amino acids at hemagglutinin cleavage site of highly pathogenic H7N9 virus promotes replication and pathogenicity in chickens and mice.

ABSTRACT: Since mid-2016, the low pathogenic H7N9 influenza virus has evolved into a highly pathogenic (HP) phenotype in China, raising many concerns about public health and poultry industry. The insertion of a "KRTA" motif at hemagglutinin cleavage site (HACS) occurred in the early stage of HP H7N9 variants. During the co-circulation, the HACS of HP-H7N9 variants were more polymorphic in birds and humans. Although HP-H7N9 variants, unlike the H5 subtype virus, exhibited the insertions of basic and non-basic amino acids, the underlying function of those insertions and substitutions remains unclear. The results of bioinformatics analysis indicated that the PEVPKRKRTAR/G motif of HACS had become the dominant motif in China. Then, we generated six H7N9 viruses bearing the PEIPKGR/G, PEVPKGR/G, PEVPKRKR

SUBMITTER: Zhou A 

PROVIDER: S-EPMC8922421 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature