Influenza A virus neuraminidase 3 (NA3)

Influenza A virus neuraminidase 3 is a viral surface enzyme belonging to the neuraminidase (NA) family, which are key glycoproteins of the influenza A virus envelope[1][2][5]. NA3 is one of nine major subtypes of neuraminidase (N1–N9) that are divided phylogenetically into two groups, with N3 in group 2[2]. The protein forms a homotetramer that displays exosialidase activity—removing terminal sialic acids from host cell receptors and newly formed viral glycoproteins[1][2][6]. This action is crucial for the release of progeny virions from the infected cell and for successful viral spread[1][5][6]. Neuraminidases are major therapeutic targets for antiviral drugs (notably oseltamivir, zanamivir, peramivir), which act by blocking the active site and thus interfering with virus dissemination[1][3][5]. Drug resistance mutations in the neuraminidase gene are a significant safety and therapeutic challenge[1][5]. NA3, like other neuraminidase subtypes, can also elicit protective antibody responses, making it a relevant immunological target[2][5].

Other names

Influenza neuraminidase N3N3 neuraminidaseNA subtype 3

Competitive inhibition of neuraminidase active site, preventing sialic acid cleavage and viral release