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Infect Genet Evol
. 2020 Dec 9;104672.
doi: 10.1016/j.meegid.2020.104672. Online ahead of print.
Deep sequencing of the transcriptome from murine lung infected with H5N8 subtype avian influenza virus with combined substitutions I283M and K526R in PB2 gene
Sujuan Chen 1 , Xiao Wang 1 , Xiang Su 1 , Xinyu Miao 1 , Tao Qin 1 , Daxin Peng 2 , Xiufan Liu 1
Affiliations
- PMID: 33309772
- DOI: 10.1016/j.meegid.2020.104672
Abstract
H5N8 subtype highly pathogenic avian influenza viruses (HPAIVs) pose a huge threat to poultry industry and general public health. Our previous study demonstrated that synergistic effect of 283M and 526R in PB2 gene was a critical factor for viral high pathogenicity in mammals. However, the potential pathogenic mechanism of the mutant virus is still unclear. Here, RNA-seq method was used to analyze the global host response of murine lungs after infecting with parental r-JY virus and JY-PB2-I283M-K526R mutant virus. We found that both amounts and the expression levels of host differentially expressed genes (DEGs) were higher in mutant virus-infected mice compared with the group of parental virus. Furthermore, the DEGs mainly related with innate immune response by GO and KEGG analysis. Especially, PB2-I283M-K526R mutation strongly induced a sharp expression of cytokine storm-related genes, including MX1, CXCL10, and IFN-γ, performed by qRT-PCR. We also found that PB2-I283M-K526R mutation accelerated the level of cell apoptosis by heat map analysis of apoptosis-related DEGs in lungs and apoptosis assay in vitro. Taken together, our data demonstrated that PB2-I283M-K526R of H5N8 subtype HPAIV exacerbated the innate immune response and the level of cell apoptosis, which might be a key pathogenic mechanism for the enhanced pathogenicity of mutants in mammals.
Keywords: Avian influenza virus; H5N8; PB2; Pathogenic mechanism; RNA-seq.