Hemagglutinin Glycoproteins, Influenza Virus

**Definition:** Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. Fourteen distinct subtypes of HA glycoproteins and nine of NA glycoproteins have been identified from INFLUENZA A VIRUS; no subtypes have been identified for Influenza B or Influenza C viruses.

**Tree numbers:** - D12.776.964.970.880.345.500