Influenza A virus neuraminidase protein subtype 1 (NA)

Influenza A virus neuraminidase protein subtype 1 is a tetrameric viral surface enzyme found on the envelope of influenza A viruses, designated as N1 in virus subtyping (e.g., H1N1). It acts as an exosialidase that cleaves terminal sialic acid residues from host cell surface glycoconjugates, enabling newly formed virus particles to detach and spread from infected cells. Each monomer contains about 470 amino acids and folds into four domains: cytoplasmic tail, transmembrane region, stalk, and catalytic "head," with active sites on the upper surface. Neuraminidase is essential for efficient viral propagation in the host and is a major antigenic determinant used for influenza virus classification. It is a proven therapeutic target, with several inhibitors in clinical use and ongoing challenges relating to resistance and antigenic variability.

Other names

Influenza A neuraminidase N1Neuraminidase N1NASialidase (less commonly)

Competitive inhibition of the neuraminidase active site, blocking cleavage of sialic acid residues and preventing release of progeny virions from infected cells