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Q9WFX3 (HEMA_I18A0) Reviewed, UniProtKB/Swiss-Prot

Last modified July 9, 2014. Version 79. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein attributes

Sequence length566 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Binds to sialic acid-containing receptors on the cell surface, bringing about the attachment of the virus particle to the cell. This attachment induces virion internalization of about two third of the virus particles through clathrin-dependent endocytosis and about one third through a clathrin- and caveolin-independent pathway. 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 induces an irreversible conformational change in HA2, releasing the fusion hydrophobic peptide. Several trimers are required to form a competent fusion pore By similarity.

Subunit structure

Homotrimer of disulfide-linked HA1-HA2 By similarity.

Subcellular location

Virion membrane; Single-pass type I membrane protein Potential. 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 By similarity.

Post-translational modification

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 Clara cells By similarity.

Palmitoylated By similarity.

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 A 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.

South Carolina isolate has been sequenced from formalid fixed-lung tissues of a 21-year-old male which died in 1918 at Ft. Jackson, SC. Brevig Mission isolate has been sequenced from lung tissues of an Inuit woman buried in the permafrost in a gravesite near Brevig Mission, Alaska. This sample was recovered by John Hultin, retired pathologist.

Sequence similarities

Belongs to the influenza viruses hemagglutinin family.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Signal peptide1 – 1717 Potential
Chain18 – 343326Hemagglutinin HA1 chain
PRO_0000310563
Chain345 – 566222Hemagglutinin HA2 chain
PRO_0000310564

Regions

Topological domain18 – 529512Extracellular Potential
Transmembrane530 – 55021Helical; Potential
Topological domain551 – 56616Cytoplasmic Potential

Sites

Site344 – 3452Cleavage; by host By similarity

Amino acid modifications

Lipidation5551S-palmitoyl cysteine; by host By similarity
Lipidation5621S-palmitoyl cysteine; by host By similarity
Lipidation5651S-palmitoyl cysteine; by host By similarity
Glycosylation271N-linked (GlcNAc...); by host Potential
Glycosylation281N-linked (GlcNAc...); by host Potential
Glycosylation401N-linked (GlcNAc...); by host Potential
Glycosylation1041N-linked (GlcNAc...); by host Potential
Glycosylation3041N-linked (GlcNAc...); by host Potential
Glycosylation4981N-linked (GlcNAc...); by host Potential
Disulfide bond21 ↔ 481Interchain (between HA1 and HA2 chains) By similarity
Disulfide bond59 ↔ 292 By similarity
Disulfide bond72 ↔ 84 By similarity
Disulfide bond107 ↔ 153 By similarity
Disulfide bond296 ↔ 320 By similarity
Disulfide bond488 ↔ 492 By similarity

Secondary structure

................................................................................................. 566
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
Q9WFX3 [UniParc].

Last modified November 13, 2007. Version 2.
Checksum: 5A292C3386E0F96B

FASTA56662,866
        10         20         30         40         50         60 
MEARLLVLLC AFAATNADTI CIGYHANNST DTVDTVLEKN VTVTHSVNLL EDSHNGKLCK 

        70         80         90        100        110        120 
LKGIAPLQLG KCNIAGWLLG NPECDLLLTA SSWSYIVETS NSENGTCYPG DFIDYEELRE 

       130        140        150        160        170        180 
QLSSVSSFEK FEIFPKTSSW PNHETTKGVT AACSYAGASS FYRNLLWLTK KGSSYPKLSK 

       190        200        210        220        230        240 
SYVNNKGKEV LVLWGVHHPP TGTDQQSLYQ NADAYVSVGS SKYNRRFTPE IAARPKVRDQ 

       250        260        270        280        290        300 
AGRMNYYWTL LEPGDTITFE ATGNLIAPWY AFALNRGSGS GIITSDAPVH DCNTKCQTPH 

       310        320        330        340        350        360 
GAINSSLPFQ NIHPVTIGEC PKYVRSTKLR MATGLRNIPS IQSRGLFGAI AGFIEGGWTG 

       370        380        390        400        410        420 
MIDGWYGYHH QNEQGSGYAA DQKSTQNAID GITNKVNSVI EKMNTQFTAV GKEFNNLERR 

       430        440        450        460        470        480 
IENLNKKVDD GFLDIWTYNA ELLVLLENER TLDFHDSNVR NLYEKVKSQL KNNAKEIGNG 

       490        500        510        520        530        540 
CFEFYHKCDD ACMESVRNGT YDYPKYSEES KLNREEIDGV KLESMGVYQI LAIYSTVASS 

       550        560 
LVLLVSLGAI SFWMCSNGSL QCRICI 

« Hide

References

[1]"Initial genetic characterization of the 1918 'Spanish' influenza virus."
Taubenberger J.K., Reid A.H., Krafft A.E., Bijwaard K.E., Fanning T.G.
Science 275:1793-1796(1997) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC RNA].
Strain: A/South Carolina/1/1918.
[2]"Origin and evolution of the 1918 'Spanish' influenza virus hemagglutinin gene."
Reid A.H., Fanning T.G., Hultin J.V., Taubenberger J.K.
Proc. Natl. Acad. Sci. U.S.A. 96:1651-1656(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC RNA], NUCLEOTIDE SEQUENCE [MRNA] OF 1-406.
Strain: A/South Carolina/1/1918.
[3]"The structure and receptor binding properties of the 1918 influenza hemagglutinin."
Gamblin S.J., Haire L.F., Russell R.J., Stevens D.J., Xiao B., Ha Y., Vasisht N., Steinhauer D.A., Daniels R.S., Elliot A., Wiley D.C., Skehel J.J.
Science 303:1838-1842(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (2.9 ANGSTROMS) OF 14-339.
Strain: A/South Carolina/1/1918.
[4]"Structure of the uncleaved human H1 hemagglutinin from the extinct 1918 influenza virus."
Stevens J., Corper A.L., Basler C.F., Taubenberger J.K., Palese P., Wilson I.A.
Science 303:1866-1870(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (3.0 ANGSTROMS) OF 18-344.
Strain: A/South Carolina/1/1918.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AF117241 Genomic RNA. Translation: AAD17229.1.
AF116575 mRNA. Translation: AAD17218.1.

3D structure databases

PDBe
RCSB-PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1RD8X-ray3.00A/C/E18-344[»]
B/D/F345-520[»]
1RUZX-ray2.90H/J/L14-339[»]
I/K/M345-504[»]
2WRGX-ray3.00H/J/L18-343[»]
I/K/M345-566[»]
3GBNX-ray2.20A18-344[»]
B345-520[»]
3LZFX-ray2.80A18-344[»]
B345-520[»]
3R2XX-ray3.10A18-344[»]
B345-520[»]
4EEFX-ray2.70A/C/E18-344[»]
B/D/F345-520[»]
4GXUX-ray3.29A/C/E/G/I/K18-344[»]
B/D/F/H/J/L345-520[»]
4GXXX-ray1.80A/C/E18-344[»]
B/D/F345-520[»]
4JUGX-ray2.70A/C/E/G/I/K18-339[»]
B/D/F/H/J/L345-514[»]
4JUHX-ray2.80A/C/E18-339[»]
B/D/F345-514[»]
4JUJX-ray3.01A/C/E18-339[»]
B/D/F345-514[»]
4PY8X-ray2.91A18-344[»]
B345-520[»]
ProteinModelPortalQ9WFX3.
SMRQ9WFX3. Positions 18-519.
ModBaseSearch...
MobiDBSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Family and domain databases

Gene3D2.10.77.10. 1 hit.
3.90.20.10. 1 hit.
3.90.209.20. 1 hit.
InterProIPR008980. Capsid_hemagglutn.
IPR013828. Hemagglutn_HA1_a/b_dom.
IPR013827. Hemagglutn_HA1_b-rbn_dom.
IPR000149. Hemagglutn_influenz_A.
IPR001364. Hemagglutn_influenz_A/B.
IPR013829. Hemagglutn_stalk.
[Graphical view]
PfamPF00509. Hemagglutinin. 1 hit.
[Graphical view]
PRINTSPR00330. HEMAGGLUTN1.
PR00329. HEMAGGLUTN12.
SUPFAMSSF49818. SSF49818. 1 hit.
ProtoNetSearch...

Other

EvolutionaryTraceQ9WFX3.

Entry information

Entry nameHEMA_I18A0
AccessionPrimary (citable) accession number: Q9WFX3
Secondary accession number(s): O10424 expand/collapse secondary AC list , O10425, O10426, Q9WFZ1
Entry history
Integrated into UniProtKB/Swiss-Prot: November 13, 2007
Last sequence update: November 13, 2007
Last modified: July 9, 2014
This is version 79 of the entry and version 2 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programViral Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references