Skip Header

You are using a version of Internet Explorer that may not display all features of this website. Please upgrade to a modern browser.
Contribute Send feedback
Read comments (?) or add your own

P03436 (HEMA_I68A6) Reviewed, UniProtKB/Swiss-Prot

Last modified February 19, 2014. Version 105. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (1) | 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

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.

Subunit structure

Homotrimer of disulfide-linked HA1-HA2. Ref.3

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.

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.

Sequence similarities

Belongs to the influenza viruses hemagglutinin family.

Sequence caution

The sequence CAA24291.1 differs from that shown. Reason: Erroneous initiation.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Signal peptide1 – 1616 Potential
Chain17 – 344328Hemagglutinin HA1 chain
PRO_0000039032
Chain346 – 566221Hemagglutinin HA2 chain
PRO_0000039033

Regions

Topological domain17 – 530514Extracellular Potential
Transmembrane531 – 55121Helical; Potential
Topological domain552 – 56615Cytoplasmic Potential

Sites

Site345 – 3462Cleavage; 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
Glycosylation241N-linked (GlcNAc...); by host Potential
Glycosylation381N-linked (GlcNAc...); by host Potential
Glycosylation541N-linked (GlcNAc...); by host Potential
Glycosylation971N-linked (GlcNAc...); by host Potential
Glycosylation1811N-linked (GlcNAc...); by host Potential
Glycosylation3011N-linked (GlcNAc...); by host Potential
Glycosylation4991N-linked (GlcNAc...); by host Potential
Disulfide bond30 ↔ 482Interchain (between HA1 and HA2 chains) Ref.3
Disulfide bond68 ↔ 293 Ref.3
Disulfide bond80 ↔ 92 Ref.3
Disulfide bond113 ↔ 155 By similarity
Disulfide bond297 ↔ 321 Ref.3
Disulfide bond489 ↔ 493 By similarity

Sequences

Sequence LengthMass (Da)Tools
P03436 [UniParc].

Last modified July 21, 1986. Version 1.
Checksum: 9A187F6A5E383671

FASTA56663,488
        10         20         30         40         50         60 
MKTIIALSYI FCLALGQDLP GNDNNTATLC LGHHAVPNGT LVKTITDDQI EVTNATELVQ 

        70         80         90        100        110        120 
SSSTGKICNN PHRILDGIDC TLIDALLGDP HCDVFQNETW DLFVERSKAF SNCYPYDVPD 

       130        140        150        160        170        180 
YASLRSLVAS SGTLEFITEG FTWTGVTQNG GSNACKRGPD SGFFSRLNWL TKSGSTYPVL 

       190        200        210        220        230        240 
NVTMPNNDNF DKLYIWGVHH PSTNQEQTSL YVQASGRVTV STRRSQQTII PNIGSRPWVR 

       250        260        270        280        290        300 
GQSSRISIYW TIVKPGDVLV INSNGNLIAP RGYFKMRTGK SSIMRSDAPI DTCISECITP 

       310        320        330        340        350        360 
NGSIPNDKPF QNVNKITYGA CPKYVKQNTL KLATGMRNVP EKQTRGLFGA IAGFIENGWE 

       370        380        390        400        410        420 
GMIDGWYGFR HQNSEGTGQA ADLKSTQAAI DQINGKLNRV IEKTNEKFHQ IEKEFSEVEG 

       430        440        450        460        470        480 
RIQDLEKYVE DTKIDLWSYN AELLVALENQ HTIDLTDSEM NKLFEKTRRQ LRENAEDMGN 

       490        500        510        520        530        540 
GCFKIYHKCD NACIESIRNG TYDHDVYRDE ALNNRFQIKG VELKSGYKDW ILWISFAISC 

       550        560 
FLLCVVLLGF IMWACQRGNI RCNICI 

« Hide

References

[1]"Complete nucleotide sequence of the haemagglutinin gene from a human influenza virus of the Hong Kong subtype."
Both G.W., Sleigh M.J.
Nucleic Acids Res. 8:2561-2575(1980) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
Strain: Subtype 29C.
[2]"The influenza virus haemagglutinin gene: cloning and characterisation of a double-stranded DNA copy."
Sleigh M.J., Both G.W., Brownlee G.G.
Nucleic Acids Res. 7:879-893(1979) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC RNA] OF 237-261.
Strain: Subtype 29C.
[3]"The disulphide bonds of a Hong Kong influenza virus hemagglutinin."
Dopheide T.A., Ward C.W.
FEBS Lett. 110:181-183(1980) [PubMed] [Europe PMC] [Abstract]
Cited for: DISULFIDE BONDS.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
V01103 mRNA. Translation: CAA24290.1. Different termination.
V01103 mRNA. Translation: CAA24291.1. Different initiation.
M25434 Genomic RNA. Translation: AAA43163.1.
PIRHMIVH. A93705.

3D structure databases

ProteinModelPortalP03436.
SMRP03436. Positions 17-520.
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...

Entry information

Entry nameHEMA_I68A6
AccessionPrimary (citable) accession number: P03436
Secondary accession number(s): Q67095, Q84107
Entry history
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 21, 1986
Last modified: February 19, 2014
This is version 105 of the entry and version 1 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