Influenza A virus neuraminidase protein subtype N2 (NA (N2))

The Influenza A virus neuraminidase protein subtype N2 is a type II transmembrane enzyme found on the viral surface, encoded by the sixth segment of the viral RNA. Neuraminidase functions as an exosialidase (EC 3.2.1.18), cleaving α-ketosidic linkages between terminal sialic acid and adjacent sugars on host glycoproteins and glycolipids. This enzymatic activity is essential for the release of new viral particles from infected cells and prevents aggregation of virions by removing sialic acids from host and viral proteins. NA exists as a homotetramer and is one of two major antigenic glycoproteins (alongside hemagglutinin) on the influenza virus surface. The NA protein is a major target for antiviral drugs such as oseltamivir, zanamivir, peramivir, and laninamivir, all of which inhibit its sialidase activity and thereby impede viral replication and spread. Rapid antigenic evolution, especially in H3N2, leads to the continual emergence of new variants, presenting challenges for therapy and vaccination. Resistance to neuraminidase inhibitors is a clinical concern, typically arising from specific amino acid mutations in the NA protein. Monitoring NA sequence and antigenicity has become increasingly important in influenza surveillance and patient management.

Other names

Neuraminidase (NA)Influenza Neuraminidase N2Sialidase (EC 3.2.1.18)Viral neuraminidaseN2 protein

Competitive inhibition of neuraminidase activity, blocking viral release from host cells