Influenza A virus neuraminidase (NA) (NA)

Influenza A virus neuraminidase (NA) is a tetrameric type II transmembrane glycoprotein and a critical enzyme in the viral life cycle (UniProt: P03468). Its primary biological function is to act as a sialidase, cleaving terminal sialic acid residues from host cell receptors and viral glycoproteins, which is essential for the release of newly formed virions from infected cells (PubMed: 29439056). Additionally, NA facilitates viral movement through the respiratory tract by degrading sialic acids present in mucus (PubMed: 30104474). While hemagglutinin (HA) is the dominant target for seasonal vaccines, NA is a major target for both antiviral drugs and vaccine-elicited antibodies that can reduce viral shedding and disease severity (PubMed: 25901139). Small-molecule inhibitors such as oseltamivir and zanamivir competitively bind to the highly conserved active site of NA to block its activity (PubChem: CID 65028). Recent vaccine strategies focus on eliciting NA-specific antibodies, which have been shown to provide broad, cross-reactive protection against multiple influenza strains (PubMed: 30104474).

Other names

SialidaseExo-alpha-sialidaseAcylneuraminyl hydrolaseViral neuraminidaseNA protein

Neuraminidase inhibitors (NAIs) bind to the enzyme's active site, preventing the cleavage of sialic acid and thus trapping virions on the host cell surface (PubChem: CID 65028). Vaccine-elicited antibodies target the NA head or stalk regions to sterically hinder enzymatic activity or trigger immune clearance via antibody-dependent cellular cytotoxicity (ADCC) (PubMed: 30104474).