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Protein

Hemagglutinin

Gene

HA

Organism
Influenza A virus (strain A/Duck/Ukraine/1/1963 H3N8)
Status
Reviewed-Annotation score: Annotation score: 4 out of 5-Experimental evidence at protein leveli

Functioni

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.

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Hemagglutinin

Keywords - Biological processi

Clathrin- and caveolin-independent endocytosis of virus by host, Clathrin-mediated endocytosis of virus by host, Fusion of virus membrane with host endosomal membrane, Fusion of virus membrane with host membrane, Host-virus interaction, Viral attachment to host cell, Viral penetration into host cytoplasm, Virus endocytosis by host, Virus entry into host cell

Names & Taxonomyi

Protein namesi
Recommended name:
Hemagglutinin
Cleaved into the following 2 chains:
Gene namesi
Name:HA
OrganismiInfluenza A virus (strain A/Duck/Ukraine/1/1963 H3N8)
Taxonomic identifieri385580 [NCBI]
Taxonomic lineageiVirusesssRNA virusesssRNA negative-strand virusesOrthomyxoviridaeInfluenzavirus A
Virus hostiAves [TaxID: 8782]
Equus caballus (Horse) [TaxID: 9796]

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini17 – 530514ExtracellularSequence analysisAdd
BLAST
Transmembranei531 – 55121HelicalSequence analysisAdd
BLAST
Topological domaini552 – 56615CytoplasmicSequence analysisAdd
BLAST

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Host cell membrane, Host membrane, Membrane, Viral envelope protein, Virion

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Signal peptidei1 – 1616Sequence analysisAdd
BLAST
Chaini17 – 344328Hemagglutinin HA1 chainPRO_0000038946Add
BLAST
Chaini346 – 566221Hemagglutinin HA2 chainPRO_0000038947Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Glycosylationi24 – 241N-linked (GlcNAc...); by hostSequence analysis
Disulfide bondi30 ↔ 482Interchain (between HA1 and HA2 chains)By similarity
Glycosylationi38 – 381N-linked (GlcNAc...); by hostSequence analysis
Glycosylationi54 – 541N-linked (GlcNAc...); by hostSequence analysis
Disulfide bondi68 ↔ 293By similarity
Disulfide bondi80 ↔ 92By similarity
Glycosylationi97 – 971N-linked (GlcNAc...); by hostSequence analysis
Disulfide bondi113 ↔ 155By similarity
Glycosylationi181 – 1811N-linked (GlcNAc...); by hostSequence analysis
Disulfide bondi297 ↔ 321By similarity
Glycosylationi301 – 3011N-linked (GlcNAc...); by hostSequence analysis
Disulfide bondi489 ↔ 493By similarity
Glycosylationi499 – 4991N-linked (GlcNAc...); by hostSequence analysis
Lipidationi555 – 5551S-palmitoyl cysteine; by hostBy similarity
Lipidationi562 – 5621S-palmitoyl cysteine; by hostBy similarity
Lipidationi565 – 5651S-palmitoyl cysteine; by hostBy similarity

Post-translational modificationi

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).By similarity
Palmitoylated.By similarity

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sitei345 – 3462Cleavage; by hostBy similarity

Keywords - PTMi

Disulfide bond, Glycoprotein, Lipoprotein, Palmitate

Interactioni

Subunit structurei

Homotrimer of disulfide-linked HA1-HA2.

Structurei

Secondary structure

1
566
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi27 – 348Combined sources
Beta strandi40 – 423Combined sources
Beta strandi48 – 536Combined sources
Beta strandi55 – 573Combined sources
Turni71 – 733Combined sources
Beta strandi74 – 763Combined sources
Helixi82 – 876Combined sources
Helixi90 – 956Combined sources
Beta strandi101 – 1055Combined sources
Helixi121 – 13111Combined sources
Beta strandi136 – 1383Combined sources
Beta strandi152 – 1576Combined sources
Beta strandi160 – 1623Combined sources
Beta strandi167 – 1693Combined sources
Beta strandi171 – 1755Combined sources
Beta strandi180 – 1856Combined sources
Beta strandi188 – 1903Combined sources
Beta strandi192 – 2009Combined sources
Helixi204 – 2118Combined sources
Beta strandi212 – 2154Combined sources
Beta strandi218 – 2214Combined sources
Beta strandi226 – 2294Combined sources
Beta strandi245 – 2539Combined sources
Beta strandi258 – 2658Combined sources
Beta strandi267 – 2704Combined sources
Beta strandi272 – 2754Combined sources
Beta strandi282 – 2854Combined sources
Beta strandi292 – 2943Combined sources
Beta strandi296 – 2994Combined sources
Beta strandi302 – 3043Combined sources
Beta strandi307 – 3115Combined sources
Beta strandi318 – 3203Combined sources
Beta strandi331 – 3333Combined sources
Turni352 – 3543Combined sources
Turni356 – 3594Combined sources
Helixi360 – 3634Combined sources
Beta strandi366 – 3738Combined sources
Beta strandi376 – 3816Combined sources
Helixi383 – 40119Combined sources
Helixi421 – 47151Combined sources
Beta strandi474 – 4774Combined sources
Beta strandi479 – 4879Combined sources
Helixi491 – 4988Combined sources
Helixi505 – 51511Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1IBNNMR-A346-365[»]
1IBONMR-A346-365[»]
1MQLX-ray2.90A/D/G17-345[»]
B/E/H346-566[»]
1MQMX-ray2.60A/D/G17-345[»]
B/E/H346-566[»]
1MQNX-ray3.20A/D/G17-345[»]
B/E/H346-566[»]
ProteinModelPortaliP03442.
SMRiP03442. Positions 25-518.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP03442.

Family & Domainsi

Sequence similaritiesi

Keywords - Domaini

Signal, Transmembrane, Transmembrane helix

Family and domain databases

Gene3Di2.10.77.10. 1 hit.
3.90.20.10. 1 hit.
3.90.209.20. 1 hit.
InterProiIPR008980. 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]
PfamiPF00509. Hemagglutinin. 1 hit.
[Graphical view]
PRINTSiPR00330. HEMAGGLUTN1.
PR00329. HEMAGGLUTN12.
SUPFAMiSSF49818. SSF49818. 1 hit.

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

P03442-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MKTVIALSYI LCLTFGQDLP GNDNSTATLC LGHHAVPNGT IVKTITDDQI
60 70 80 90 100
EVTNATELVQ SSSTGKICNN PHRILDGRAC TLIDALLGDP HCDVFQNETW
110 120 130 140 150
DLFVERSNAF SNCYPYDIPD YASLRSLVAS SGTLEFITEG FTWTGVTQNG
160 170 180 190 200
GSSACKRGPA NGFFSRLNWL TKSESAYPVL NVTMPNNDNF DKLYIWGVHH
210 220 230 240 250
PSTNQEQTNL YVQASGRVTV STRRSQQTII PNIGSRPWVR GQPGRISIYW
260 270 280 290 300
TIVKPGDVLV INSNGNLIAP RGYFKMRTGK SSIMRSDAPI DTCISECITP
310 320 330 340 350
NGSIPNDKPF QNVNKITYGA CPKYVKQNTL KLATGMRNVP EKQTRGLFGA
360 370 380 390 400
IAGFIENGWE GMIDGWYGFR HQNSEGTGQA ADLKSTQAAI DQINRKLNRV
410 420 430 440 450
IEKTNEKFHQ IEKEFSEVEG RIQDLEKYVE DTKIDLWSYN AELLVALENQ
460 470 480 490 500
HTIDLADSEM NKLFEKTRRQ LRENAEDMGN GCFKIYHKCD NACIESIRNG
510 520 530 540 550
TYDHDIYRDE ALNNRFQIKG VELKSGYKDW ILWISFAISC LLLCVVLLGF
560
IMWACQRGNI RCNICI
Length:566
Mass (Da):63,530
Last modified:July 21, 1986 - v1
Checksum:iE70F87F0AE1178F4
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
V01087 Unassigned RNA. Translation: CAA24271.1.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
V01087 Unassigned RNA. Translation: CAA24271.1.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1IBNNMR-A346-365[»]
1IBONMR-A346-365[»]
1MQLX-ray2.90A/D/G17-345[»]
B/E/H346-566[»]
1MQMX-ray2.60A/D/G17-345[»]
B/E/H346-566[»]
1MQNX-ray3.20A/D/G17-345[»]
B/E/H346-566[»]
ProteinModelPortaliP03442.
SMRiP03442. Positions 25-518.
ModBaseiSearch...
MobiDBiSearch...

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Miscellaneous databases

EvolutionaryTraceiP03442.

Family and domain databases

Gene3Di2.10.77.10. 1 hit.
3.90.20.10. 1 hit.
3.90.209.20. 1 hit.
InterProiIPR008980. 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]
PfamiPF00509. Hemagglutinin. 1 hit.
[Graphical view]
PRINTSiPR00330. HEMAGGLUTN1.
PR00329. HEMAGGLUTN12.
SUPFAMiSSF49818. SSF49818. 1 hit.
ProtoNetiSearch...

Entry informationi

Entry nameiHEMA_I63A3
AccessioniPrimary (citable) accession number: P03442
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 21, 1986
Last modified: October 14, 2015
This is version 112 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programViral Protein Annotation Program

Miscellaneousi

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.

Keywords - Technical termi

3D-structure

Documents

  1. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  2. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.