Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.

The annotation and conditions in this rule are derived from the following entries: P03452 (HEMA_I34A1), P03465 (HEMA_INCCA)

If a protein meets these conditions... i

Common conditions

Special conditions

    • taxon = Gammainfluenzavirus
    • Subsequence at position 15 - 40 aligns to entry P03465 (individually applies "Fusion domain-1")
    • Subsequence at position 20 - 583 aligns to "C-x*-C" in entry P03465 (individually applies "Interchain (between HEF1 and HEF2 chains)")
    • Subsequence at position 41 - 150 aligns to entry P03465 (individually applies "Esterase domain-1")
    • Subsequence at position 71 - 71 aligns to entry P03465 (individually applies "Nucleophile")
    • Subsequence at position 120 - 165 aligns to "C-x*-C" in entry P03465 (individually applies "")
    • Subsequence at position 140 - 188 aligns to "C-x*-C" in entry P03465 (individually applies "")
    • Subsequence at position 150 - 310 aligns to entry P03465 (individually applies "N-acetyl-9-O-acetylneuraminic acid binding")
    • Subsequence at position 210 - 252 aligns to "C-x*-C" in entry P03465 (individually applies "")
    • Subsequence at position 229 - 316 aligns to "C-x*-C" in entry P03465 (individually applies "")
    • Subsequence at position 237 - 289 aligns to "C-x*-C" in entry P03465 (individually applies "")
    • Subsequence at position 310 - 364 aligns to entry P03465 (individually applies "Esterase domain-2")
    • Subsequence at position 345 - 351 aligns to "C-x*-C" in entry P03465 (individually applies "")
    • Subsequence at position 365 - 650 aligns to entry P03465 (individually applies "Fusion domain-2")
    • Subsequence at position 366 - 366 aligns to entry P03465 (individually applies "Charge relay system")
    • Subsequence at position 369 - 369 aligns to entry P03465 (individually applies "Charge relay system")
    • taxon = Betainfluenzavirus, Alphainfluenzavirus
    • Subsequence at position 21 - 480 aligns to "C-x*-C" in entry P03452 (individually applies "Interchain (between HA1 and HA2 chains)")
    • Subsequence at position 59 - 291 aligns to "C-x*-C" in entry P03452 (individually applies "")
    • Subsequence at position 72 - 84 aligns to "C-x*-C" in entry P03452 (individually applies "")
    • Subsequence at position 107 - 152 aligns to "C-x*-C" in entry P03452 (individually applies "")
    • Subsequence at position 295 - 319 aligns to "C-x*-C" in entry P03452 (individually applies "")
    • Subsequence at position 343 - 344 aligns to "R-G" in entry P03452 (individually applies "Cleavage; by host")
    • Subsequence at position 487 - 491 aligns to "C-x*-C" in entry P03452 (individually applies "")
    • Subsequence at position 554 - 554 aligns to "C" in entry P03452 (individually applies "S-palmitoyl cysteine; by host")
    • Subsequence at position 561 - 561 aligns to "C" in entry P03452 (individually applies "S-palmitoyl cysteine; by host")
    • Subsequence at position 564 - 564 aligns to "C" in entry P03452 (individually applies "S-palmitoyl cysteine; by host")
    • Predicted signal
    • Predicted transmembrane

... then these annotations are applied i

Protein namesi

  • Recommended name:
    Hemagglutinin
  • Recommended name:
    Hemagglutinin-esterase-fusion glycoprotein (EC:3.1.1.53)
    Short name:
    HEF

Cleaved chain(s) or included domain(s)i

  • Cleaved chain:
    Recommended name:
    Hemagglutinin HA1 chain
  • Cleaved chain:
    Recommended name:
    Hemagglutinin HA2 chain
  • Cleaved chain:
    Recommended name:
    Hemagglutinin-esterase-fusion glycoprotein chain 1
    Short name:
    HEF1
  • Cleaved chain:
    Recommended name:
    Hemagglutinin-esterase-fusion glycoprotein chain 2
    Short name:
    HEF2

Gene namesi

  • Name:HA
  • Name:HE

Functioni

  • 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.
  • Binds to the N-acetyl-9-O-acetylneuraminic acid residues 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 HEF2, releasing the fusion hydrophobic peptide. Several trimers are required to form a competent fusion pore. Displays a receptor-destroying activity which is a neuraminidate-O-acetyl esterase. This activity cleaves off any receptor on the cell surface, which would otherwise prevent virions release. These cleavages prevent self-aggregation and ensure the efficient spread of the progeny virus from cell to cell.
  • 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 either through clathrin-dependent endocytosis or through 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.

Subcellular locationi

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.
  • Palmitoylated.
  • In natural infection, inactive HEF is matured into HEF1 and HEF2 outside the cell by one or more trypsin-like, arginine-specific endoprotease.
  • 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.
  • Palmitoylated.

Sequence similaritiesi

Catalytic activityi

  • N-acetyl-O-acetylneuraminate + H2O = N-acetylneuraminate + acetate.

Subunit structurei

  • Homotrimer of disulfide-linked HA1-HA2.
  • Homotrimer of disulfide-linked HEF1-HEF2.
  • Homotrimer of disulfide-linked HA1-HA2.

Transmembranei

  • Helical (to residues corresponding to positions @FROM@i - @TO@i)

Active sitei

  • Nucleophile (to residues corresponding to position 71)
  • Charge relay system (to residues corresponding to position 366)
  • Charge relay system (to residues corresponding to position 369)

Regioni

  • Fusion domain-1 (to residues corresponding to positions 15 - 40)
  • Esterase domain-1 (to residues corresponding to positions 41 - 150)
  • N-acetyl-9-O-acetylneuraminic acid binding (to residues corresponding to positions 150 - 310)
  • Esterase domain-2 (to residues corresponding to positions 310 - 364)
  • Fusion domain-2 (to residues corresponding to positions 365 - 650)

Chaini

  • @CHAIN_NAME@i (to residues corresponding to positions @TO|+1@i - @CTER@i)

Disulfide bondi

  • Interchain (between HEF1 and HEF2 chains) (to residues corresponding to positions 20 - 583)
  • (to residues corresponding to positions 120 - 165)
  • (to residues corresponding to positions 140 - 188)
  • (to residues corresponding to positions 210 - 252)
  • (to residues corresponding to positions 229 - 316)
  • (to residues corresponding to positions 237 - 289)
  • (to residues corresponding to positions 345 - 351)
  • Interchain (between HA1 and HA2 chains) (to residues corresponding to positions 21 - 480)
  • (to residues corresponding to positions 59 - 291)
  • (to residues corresponding to positions 72 - 84)
  • (to residues corresponding to positions 107 - 152)
  • (to residues corresponding to positions 295 - 319)
  • (to residues corresponding to positions 487 - 491)

Sitei

  • Cleavage; by host (to residues corresponding to positions 343 - 344)

Signal peptidei

  • (to residues corresponding to positions @NTER@i - @TO@i)

Lipidationi

  • S-palmitoyl cysteine; by host (to residues corresponding to position 554)
  • S-palmitoyl cysteine; by host (to residues corresponding to position 561)
  • S-palmitoyl cysteine; by host (to residues corresponding to position 564)

Keywordsi

GO (Gene Ontology) termsi

We'd like to inform you that we have updated our Privacy Notice to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.

Do not show this banner again
UniProt is an ELIXIR core data resource
Main funding by: National Institutes of Health