P17504 · HEMA_INBBE
- ProteinHemagglutinin
- GeneHA
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids585 (go to sequence)
- Protein existenceInferred from homology
- Annotation score4/5
Function
function
Binds to sialic acid-containing receptors on the cell surface, bringing about the attachment of the virus particle to the cell. Plays a major role in the determination of host range restriction and virulence. Class I viral fusion protein. Responsible for penetration of the virus into the cell cytoplasm by mediating the fusion of the membrane of the endocytosed virus particle with the endosomal membrane. Low pH in endosomes induce an irreversible conformational change in HA2, releasing the fusion hydrophobic peptide. Several trimers are required to form a competent fusion pore.
Miscellaneous
Major glycoprotein, comprises over 80% of the envelope proteins present in virus particle.
The extent of infection into host organism is determined by HA. Influenza viruses bud from the apical surface of polarized epithelial cells (e.g. bronchial epithelial cells) into lumen of lungs and are therefore usually pneumotropic. The reason is that HA is cleaved by tryptase clara which is restricted to lungs. However, HAs of H5 and H7 pantropic avian viruses subtypes can be cleaved by furin and subtilisin-type enzymes, allowing the virus to grow in other organs than lungs.
The influenza B genome consist of 8 RNA segments. Genetic variation of hemagglutinin and/or neuraminidase genes results in the emergence of new influenza strains. The mechanism of variation can be the result of point mutations or the result of genetic reassortment between segments of two different strains.
Features
Showing features for site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Site | 362-363 | Cleavage; by host | ||||
Sequence: RG |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | host cell plasma membrane | |
Cellular Component | membrane | |
Cellular Component | viral envelope | |
Cellular Component | virion membrane | |
Molecular Function | host cell surface receptor binding | |
Biological Process | endocytosis involved in viral entry into host cell | |
Biological Process | fusion of virus membrane with host endosome membrane | |
Biological Process | fusion of virus membrane with host plasma membrane | |
Biological Process | viral budding from plasma membrane | |
Biological Process | virion attachment to host cell |
Keywords
- Molecular function
- Biological process
Names & Taxonomy
Protein names
- Recommended nameHemagglutinin
- Cleaved into 2 chains
Gene names
Organism names
- Taxonomic lineageViruses > Riboviria > Orthornavirae > Negarnaviricota > Polyploviricotina > Insthoviricetes > Articulavirales > Orthomyxoviridae > Betainfluenzavirus > Betainfluenzavirus influenzae > Influenza B virus
- Virus hosts
Accessions
- Primary accessionP17504
Subcellular Location
UniProt Annotation
GO Annotation
Virion membrane ; Single-pass type I membrane protein
Host apical cell membrane ; Single-pass type I membrane protein
Note: Targeted to the apical plasma membrane in epithelial polarized cells through a signal present in the transmembrane domain. Associated with glycosphingolipid- and cholesterol-enriched detergent-resistant lipid rafts.
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Topological domain | 16-553 | Extracellular | ||||
Sequence: DRICTGITSSNSPHVVKTATQGEVNVTGVIPLTTTPTKSHFANLKGTKTRGKLCPKCLNCTDLDVALGRPKCMGTIPSAKASILHEVKPVTSGCFPIMHDRTKIRQLPNLLRGYEHIRLSTHNVINAETAPGGPYKVGTSGSCPNVTNGNGFFATMAWAVPKNDNNKTATNPLTVEVPYICTEGEDQITVWGFHSDNEAQMVKLYGDSKPQKFTSSANGVTTHYVSQIGGFPNQAEDGGLPQSGRIVVDYMVQKSGKTGTITYQRGILLPQKVWCASGRSKVIKGSLPLIGERDCLHEKYGGLNKSKPYYTGEHAKAIGNCPIWVKTPLKLANGTKYRPPAKLLKERGFFGAIAGFLEGGWEGMIAGWHGYTSHGAHGVAVAADLKSTQEAINKITKNLNSLSELEVKNLQRLSGAMDELHNEILELDEKVDDLRADTISSQIELAVLLSNEGIINSEDEHLLALERKLKKMLGPSAVDIGNGCFETKHKCNQTCLDRIAAGTFNAGEFSLPTFDSLNITAASLNDDGLDNHTILLYY | ||||||
Transmembrane | 554-574 | Helical | ||||
Sequence: STAASSLAVTLMIAIFIVYMV | ||||||
Topological domain | 575-585 | Cytoplasmic | ||||
Sequence: SRDNVSCSICL |
Keywords
- Cellular component
PTM/Processing
Features
Showing features for signal, chain, disulfide bond, glycosylation, lipidation.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Signal | 1-15 | |||||
Sequence: MKAIIVLLMVVTSNA | ||||||
Chain | PRO_0000440545 | 16-361 | Hemagglutinin HA1 chain | |||
Sequence: DRICTGITSSNSPHVVKTATQGEVNVTGVIPLTTTPTKSHFANLKGTKTRGKLCPKCLNCTDLDVALGRPKCMGTIPSAKASILHEVKPVTSGCFPIMHDRTKIRQLPNLLRGYEHIRLSTHNVINAETAPGGPYKVGTSGSCPNVTNGNGFFATMAWAVPKNDNNKTATNPLTVEVPYICTEGEDQITVWGFHSDNEAQMVKLYGDSKPQKFTSSANGVTTHYVSQIGGFPNQAEDGGLPQSGRIVVDYMVQKSGKTGTITYQRGILLPQKVWCASGRSKVIKGSLPLIGERDCLHEKYGGLNKSKPYYTGEHAKAIGNCPIWVKTPLKLANGTKYRPPAKLLKE | ||||||
Chain | PRO_0000440544 | 16-585 | Hemagglutinin | |||
Sequence: DRICTGITSSNSPHVVKTATQGEVNVTGVIPLTTTPTKSHFANLKGTKTRGKLCPKCLNCTDLDVALGRPKCMGTIPSAKASILHEVKPVTSGCFPIMHDRTKIRQLPNLLRGYEHIRLSTHNVINAETAPGGPYKVGTSGSCPNVTNGNGFFATMAWAVPKNDNNKTATNPLTVEVPYICTEGEDQITVWGFHSDNEAQMVKLYGDSKPQKFTSSANGVTTHYVSQIGGFPNQAEDGGLPQSGRIVVDYMVQKSGKTGTITYQRGILLPQKVWCASGRSKVIKGSLPLIGERDCLHEKYGGLNKSKPYYTGEHAKAIGNCPIWVKTPLKLANGTKYRPPAKLLKERGFFGAIAGFLEGGWEGMIAGWHGYTSHGAHGVAVAADLKSTQEAINKITKNLNSLSELEVKNLQRLSGAMDELHNEILELDEKVDDLRADTISSQIELAVLLSNEGIINSEDEHLLALERKLKKMLGPSAVDIGNGCFETKHKCNQTCLDRIAAGTFNAGEFSLPTFDSLNITAASLNDDGLDNHTILLYYSTAASSLAVTLMIAIFIVYMVSRDNVSCSICL | ||||||
Disulfide bond | 19↔499 | Interchain (between HA1 and HA2 chains) | ||||
Sequence: CTGITSSNSPHVVKTATQGEVNVTGVIPLTTTPTKSHFANLKGTKTRGKLCPKCLNCTDLDVALGRPKCMGTIPSAKASILHEVKPVTSGCFPIMHDRTKIRQLPNLLRGYEHIRLSTHNVINAETAPGGPYKVGTSGSCPNVTNGNGFFATMAWAVPKNDNNKTATNPLTVEVPYICTEGEDQITVWGFHSDNEAQMVKLYGDSKPQKFTSSANGVTTHYVSQIGGFPNQAEDGGLPQSGRIVVDYMVQKSGKTGTITYQRGILLPQKVWCASGRSKVIKGSLPLIGERDCLHEKYGGLNKSKPYYTGEHAKAIGNCPIWVKTPLKLANGTKYRPPAKLLKERGFFGAIAGFLEGGWEGMIAGWHGYTSHGAHGVAVAADLKSTQEAINKITKNLNSLSELEVKNLQRLSGAMDELHNEILELDEKVDDLRADTISSQIELAVLLSNEGIINSEDEHLLALERKLKKMLGPSAVDIGNGC | ||||||
Glycosylation | 40 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Glycosylation | 74 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Disulfide bond | 75↔87 | |||||
Sequence: CTDLDVALGRPKC | ||||||
Disulfide bond | 109↔158 | |||||
Sequence: CFPIMHDRTKIRQLPNLLRGYEHIRLSTHNVINAETAPGGPYKVGTSGSC | ||||||
Glycosylation | 160 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Glycosylation | 181 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Glycosylation | 319 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Glycosylation | 348 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Chain | PRO_0000039087 | 363-585 | Hemagglutinin HA2 chain | |||
Sequence: GFFGAIAGFLEGGWEGMIAGWHGYTSHGAHGVAVAADLKSTQEAINKITKNLNSLSELEVKNLQRLSGAMDELHNEILELDEKVDDLRADTISSQIELAVLLSNEGIINSEDEHLLALERKLKKMLGPSAVDIGNGCFETKHKCNQTCLDRIAAGTFNAGEFSLPTFDSLNITAASLNDDGLDNHTILLYYSTAASSLAVTLMIAIFIVYMVSRDNVSCSICL | ||||||
Disulfide bond | 506↔510 | |||||
Sequence: CNQTC | ||||||
Glycosylation | 507 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Glycosylation | 533 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Glycosylation | 546 | N-linked (GlcNAc...) asparagine; by host | ||||
Sequence: N | ||||||
Lipidation | 581 | S-palmitoyl cysteine; by host | ||||
Sequence: C | ||||||
Lipidation | 584 | S-palmitoyl cysteine; by host | ||||
Sequence: C |
Post-translational modification
Palmitoylated.
In natural infection, inactive HA is matured into HA1 and HA2 outside the cell by one or more trypsin-like, arginine-specific endoprotease secreted by the bronchial epithelial cells. One identified protease that may be involved in this process is secreted in lungs by club cells.
Keywords
- PTM
PTM databases
Interaction
Subunit
Homotrimer of disulfide-linked HA1-HA2.
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length585
- Mass (Da)63,166
- Last updated1990-08-01 v1
- Checksum129987C8572F9176