Neuraminidase (Influenza A virus subtype H7N9) (NA)

Neuraminidase (NA) is a critical surface glycoprotein of the H7N9 influenza A virus, functioning as a sialidase enzyme that facilitates viral propagation. Its primary biological role involves the cleavage of terminal sialic acid residues from host cell receptors and nascent viral glycoproteins, which is essential for the release of progeny virions from the host cell surface (UniProt P0C6Y6). By preventing the aggregation of new viruses and allowing them to penetrate the respiratory mucus layer, NA ensures the efficient spread of infection throughout the respiratory tract (PubMed: 23670586). In the context of H7N9, a subtype of avian influenza that has caused severe human infections with high mortality, NA serves as a major target for therapeutic intervention (CDC). Current antiviral treatments, including oseltamivir, zanamivir, and peramivir, function by binding to the highly conserved active site of the neuraminidase enzyme, thereby inhibiting its catalytic activity and halting the viral life cycle (Nature: 10.1038/nature12114). However, the clinical utility of these drugs is threatened by the emergence of specific amino acid substitutions, such as the R292K mutation, which significantly reduce drug sensitivity (The Lancet: 10.1016/S0140-6736(13)61125-4). Understanding the structural and functional characteristics of H7N9 neuraminidase remains vital for the development of more resilient antiviral strategies and for monitoring the pandemic potential of this virus.

Other names

SialidaseN9 neuraminidaseH7N9 NAExosialidaseAcylneuraminyl hydrolase

Neuraminidase inhibitors competitively bind to the enzyme's active site, preventing the cleavage of terminal sialic acid residues on host cell surfaces and viral glycoproteins, which traps progeny virions at the cell surface and inhibits viral spread (Nature: 10.1038/nature12114).