| Hemagglutinin | |||||||||
|---|---|---|---|---|---|---|---|---|---|
&sq=&lang=&file=File:PDB_1hgd_EBI.jpg) | |||||||||
| Identifiers | |||||||||
| Symbol | Hemagglutinin | ||||||||
| Pfam | PF00509 | ||||||||
| InterPro | IPR001364 | ||||||||
| SCOP2 | 1hgd / SCOPe / SUPFAM | ||||||||
| OPM superfamily | 109 | ||||||||
| OPM protein | 6hjq | ||||||||
| |||||||||
| Influenza C hemagglutinin stalk | |||||||||
|---|---|---|---|---|---|---|---|---|---|
&sq=&lang=&file=File:PDB_1flc_EBI.jpg) x-ray structure of the haemagglutinin-esterase-fusion glycoprotein of influenza c virus | |||||||||
| Identifiers | |||||||||
| Symbol | Hema_stalk | ||||||||
| Pfam | PF08720 | ||||||||
| InterPro | IPR014831 | ||||||||
| SCOP2 | 1flc / SCOPe / SUPFAM | ||||||||
| OPM superfamily | 277 | ||||||||
| OPM protein | 2jrd | ||||||||
| |||||||||
Influenza hemagglutinin (HA) or haemagglutinin[p] (British English) is a homotrimeric glycoprotein found on the surface of influenza viruses and is integral to its infectivity.
Hemagglutinin is a class I fusion protein,[1][2] having multifunctional activity as both an attachment factor and membrane fusion protein. Therefore, HA is responsible for binding influenza viruses to sialic acid on the surface of target cells, such as cells in the upper respiratory tract or erythrocytes,[3] resulting in the internalization of the virus.[4] Additionally, HA is responsible for the fusion of the viral envelope with the late endosomal membrane once exposed to low pH (5.0–5.5).[5]
The name "hemagglutinin" comes from the protein's ability to cause red blood cells (i.e., erythrocytes) to clump together (i.e., agglutinate) in vitro.[6]
- ^ Skehel JJ, Wiley DC (July 2000). "Receptor binding and membrane fusion in virus entry: the influenza hemagglutinin". Annual Review of Biochemistry. 69. Annual Reviews: 531–569. doi:10.1146/annurev.biochem.69.1.531. PMID 10966468.
- ^ Kielian M, Rey FA (January 2006). "Virus membrane-fusion proteins: more than one way to make a hairpin". Nature Reviews. Microbiology. 4 (1): 67–76. doi:10.1038/nrmicro1326. PMC 7097298. PMID 16357862.
- ^ Russell RJ, Kerry PS, Stevens DJ, Steinhauer DA, Martin SR, Gamblin SJ, et al. (November 2008). "Structure of influenza hemagglutinin in complex with an inhibitor of membrane fusion". Proceedings of the National Academy of Sciences of the United States of America. 105 (46): 17736–17741. Bibcode:2008PNAS..10517736R. doi:10.1073/pnas.0807142105. PMC 2584702. PMID 19004788.
- ^ Edinger TO, Pohl MO, Stertz S (February 2014). "Entry of influenza A virus: host factors and antiviral targets". The Journal of General Virology. 95 (Pt 2): 263–277. doi:10.1099/vir.0.059477-0. PMID 24225499.
- ^ Banerjee I, Yamauchi Y, Helenius A, Horvath P (12 July 2013). "High-content analysis of sequential events during the early phase of influenza A virus infection". PLOS ONE. 8 (7): e68450. Bibcode:2013PLoSO...868450B. doi:10.1371/journal.pone.0068450. PMC 3709902. PMID 23874633.
- ^ Nelson DL, Cox MM (2005). Lehninger's Principles of Biochemistry (4th ed.). New York: WH Freeman.