Haemagglutinin-neuraminidase (IPR000665)

Short name: Hemagglutn-neuramid

Family relationships


This entry represents the haemagglutinin-neuraminidase (HN) glycoprotein found in a variety of paramyxoviruses (negative-stranded RNA viruses), including Mumps virus, Human parainfluenza virus 3, and the avian pathogen Newcastle disease virus. The paramyxoviruses have two surface glycoproteins, HN and a fusion protein (F). HN is a multi-functional protein with three distinct functions: a receptor-binding (haemagglutinin) activity, a receptor-destroying (neuraminidase) activity, and a membrane fusion activity that fuses the viral envelope to the host cell membrane in order to infect the cell. The fusion activity involves an interaction between HN and the fusion protein. In other viruses, such as influenza A and B viruses, haemagglutinin and neuraminidase occur as separate glycoproteins.

The haemagglutinin-neuraminidase glycoprotein has a six-bladed beta-propeller structure, and bears structural similarity to influenza A and B virus neuraminidase, bacterial neuraminidase, trypanosomal neuraminidase and transialidase [PMID: 15016893, PMID: 14729348].

More information about haemagglutinin proteins can be found at Protein of the Month: Bird Flu, Haemagglutinin [].

GO terms

Biological Process

GO:0019058 viral life cycle

Molecular Function

GO:0004308 exo-alpha-sialidase activity
GO:0046789 host cell surface receptor binding

Cellular Component

GO:0019031 viral envelope

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.