|BRIGGS, KELSEY - Orise Fellow|
Submitted to: Frontiers in Veterinary Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/21/2023
Publication Date: N/A
Interpretive Summary: Avian influenza is disease caused by infection with avian influenza virus (AIV). These viruses are naturally found in wild aquatic birds and can infect domestic poultry causing significant mortality and financial losses. AIVs do not normally infect mammals, however, recent outbreaks have demonstrated the ability to jump into other species. In these studies, we examine markers of adaption. We demonstrate that recent isolates of AIV have increased isolations in mammalian species. We also demonstrate that variability is found within the PB2 gene regardless of the species from the isolates originated. Taken together, these studies broaden our understanding of AIV adaption in other species.
Technical Abstract: Avian influenza viruses (AIV) are naturally found in wild birds, primarily in migratory waterfowl. Although species barriers exist, many AIV have demonstrated the ability to jump from birds into mammalian species. A key contributor to this jump is adaption of the viral RNA polymerase complex to its new host for efficient replication of its RNA genome. The AIV PB2 gene appears to be essential in this conversion as key residues have been discovered at amino acid position 627 that interact with the host cellular protein, acidic nuclear phosphoprotein 32 (ANP32). In particular, the conversion of glutamic acid (E) to a lysine (K) is frequently observed at this position following isolation in mammals. The focus of this report was to compare the distribution of PB2 627 residues from different lineages and origins of H5 AIV, determine the prevalence between historical and contemporary isolates, and investigate the ratio of amino acids in avian-isolated versus mammalian-isolated AIV. Results demonstrate a low prevalence of E627K in H5 non-Goose/Guangdong/1996-lineage (Gs-GD) AIV samples, with very low numbers of mammalian isolates in general. In contrast, increased prevalence of E627K was observed in the H5-Gs/GD lineage which contained significantly more total isolates, including increased numbers of mammalian isolates. An approximate 40 percent conversion of E to K was observed in mammalian isolates of H5 AIV, suggesting a non-exclusive requirement. Taken together, these results expand our understanding of the distribution of these residues within different subtypes of AIV and aid in our knowledge of PB2 mutations in different species.