Hemagglutinin-neuraminidase refers to a single viral protein that has both hemagglutinin and (endo) neuraminidaseEC3.2.1.18 activity. This is in contrast to the proteins found in influenza, where both functions exist but in two separate proteins. Its neuraminidase domain has the CAZy designation glycoside hydrolase family 83 (GH83).[2]
It does show a structural similarity to influenza viral neuraminidase and has a six-bladed beta-propeller structure.[3] This Pfam entry also matches measles hemagglutinin (cd15467), which has a "dead" neuraminidase part repurposed as a receptor binding site.[4]
^Lawrence MC, Borg NA, Streltsov VA, et al. (January 2004). "Structure of the haemagglutinin-neuraminidase from human parainfluenza virus type III". J. Mol. Biol. 335 (5): 1343–57. doi:10.1016/j.jmb.2003.11.032. PMID14729348.