hemagglutinin-neuraminidase
{{Infobox protein family
| Symbol = HN
| Name = Hemagglutinin-neuraminidase, Paramyxoviridae
| image = PDB 1usr EBI.jpg
| width =
| caption = Structure of the sialic acid binding site in Newcastle disease virus hemagglutinin-neuraminidase.{{cite journal |vauthors=Zaitsev V, von Itzstein M, Groves D, etal |title=Second sialic acid binding site in Newcastle disease virus hemagglutinin-neuraminidase: implications for fusion |journal=J. Virol. |volume=78 |issue=7 |pages=3733–41 |date=April 2004 |pmid=15016893 |pmc=371092 |doi= 10.1128/JVI.78.7.3733-3741.2004}}
| Pfam = PF00423
| Pfam_clan = CL0434
| InterPro = IPR000665
| SMART =
| PROSITE =
| MEROPS =
| SCOP = 1usr
| TCDB =
| OPM family =
| OPM protein =
| CAZy = GH83
| CDD = cd15469
| PDB = {{PDB2|1e8t}}, {{PDB2|1e8u}}, {{PDB2|1e8v}}, {{PDB2|1usr}}, {{PDB2|1usx}}, {{PDB2|1v2i}}, {{PDB2|1v3b}}, {{PDB2|1v3c}}, {{PDB2|1v3d}}, {{PDB2|1v3e}}
}}
Hemagglutinin-neuraminidase refers to a single viral protein that has both hemagglutinin and (endo) neuraminidase {{EC number|3.2.1.18}} 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).{{cite journal|vauthors=Yuan P, Thompson TB, Wurzburg BA, Paterson RG, Lamb RA, Jardetzky TS | title=Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. | journal=Structure | year= 2005 | volume= 13 | issue= 5 | pages= 803–15 | pmid=15893670 | doi=10.1016/j.str.2005.02.019 | doi-access=free }}
It does show a structural similarity to influenza viral neuraminidase and has a six-bladed beta-propeller structure.{{cite journal |vauthors=Lawrence MC, Borg NA, Streltsov VA, etal |title=Structure of the haemagglutinin-neuraminidase from human parainfluenza virus type III |journal=J. Mol. Biol. |volume=335 |issue=5 |pages=1343–57 |date=January 2004 |pmid=14729348 |doi= 10.1016/j.jmb.2003.11.032}} This Pfam entry also matches measles hemagglutinin (cd15467), which has a "dead" neuraminidase part repurposed as a receptor binding site.{{cite journal |last1=Colf |first1=LA |last2=Juo |first2=ZS |last3=Garcia |first3=KC |title=Structure of the measles virus hemagglutinin. |journal=Nature Structural & Molecular Biology |date=December 2007 |volume=14 |issue=12 |pages=1227–8 |doi=10.1038/nsmb1342 |pmid=18026116|s2cid=40292 }}
Hemagglutinin-neuraminidase allows the virus to stick to a potential host cell, and cut itself loose if necessary. Hemagglutinin-neuraminidase can be found in a variety of paramyxoviruses including mumps virus, human parainfluenza virus 3, and the avian pathogen Newcastle disease virus.
Types include:
Hemagglutinin-neuraminidase inhibitors have been investigated and suggest that there may applications for human use in the future.{{cite journal |vauthors=Alymova IV, Taylor G, Takimoto T, etal |title=Efficacy of novel hemagglutinin-neuraminidase inhibitors BCX 2798 and BCX 2855 against human parainfluenza viruses in vitro and in vivo |journal=Antimicrob. Agents Chemother. |volume=48 |issue=5 |pages=1495–502 |date=May 2004 |pmid=15105096 |pmc=400544 |doi= 10.1128/AAC.48.5.1495-1502.2004}}
References
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{{Viral proteins}}
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