ID Q2LCW8_9INFA Unreviewed; 328 AA. AC Q2LCW8; DT 21-FEB-2006, integrated into UniProtKB/TrEMBL. DT 21-FEB-2006, sequence version 1. DT 22-NOV-2017, entry version 72. DE RecName: Full=Hemagglutinin {ECO:0000256|SAAS:SAAS00070811}; DE Flags: Fragment; GN Name=HA1 {ECO:0000313|EMBL:ABC66254.1}; OS Influenza A virus (A/Brazil/10/2000(H3N2)). OC Viruses; ssRNA viruses; ssRNA negative-strand viruses; OC Orthomyxoviridae; Influenzavirus A. OX NCBI_TaxID=1598360 {ECO:0000313|EMBL:ABC66254.1}; RN [1] {ECO:0000313|EMBL:ABC66254.1} RP NUCLEOTIDE SEQUENCE. RC STRAIN=A/Brazil/010/00 {ECO:0000313|EMBL:ABC66254.1}; RA Golono M.A., Mayer M.G., Pereira A., Oliveira D.B.L., Araujo J., RA Vallada M.G., Durigon E.L., Becak W.; RT "Influenza A hemagglutinin variant, H3N2 subtype (HA1)."; RL Submitted (DEC-2005) to the EMBL/GenBank/DDBJ databases. CC -!- FUNCTION: Binds to sialic acid-containing receptors on the cell CC surface, bringing about the attachment of the virus particle to CC the cell. This attachment induces virion internalization either CC through clathrin-dependent endocytosis or through clathrin- and CC caveolin-independent pathway. Plays a major role in the CC determination of host range restriction and virulence. Class I CC viral fusion protein. Responsible for penetration of the virus CC into the cell cytoplasm by mediating the fusion of the membrane of CC the endocytosed virus particle with the endosomal membrane. Low pH CC in endosomes induces an irreversible conformational change in HA2, CC releasing the fusion hydrophobic peptide. Several trimers are CC required to form a competent fusion pore. CC {ECO:0000256|SAAS:SAAS00842036}. CC -!- FUNCTION: Binds to sialic acid-containing receptors on the cell CC surface, bringing about the attachment of the virus particle to CC the cell. This attachment induces virion internalization of about CC two third of the virus particles through clathrin-dependent CC endocytosis and about one third through a clathrin- and caveolin- CC independent pathway. Plays a major role in the determination of CC host range restriction and virulence. Class I viral fusion CC protein. Responsible for penetration of the virus into the cell CC cytoplasm by mediating the fusion of the membrane of the CC endocytosed virus particle with the endosomal membrane. Low pH in CC endosomes induces an irreversible conformational change in HA2, CC releasing the fusion hydrophobic peptide. Several trimers are CC required to form a competent fusion pore. CC {ECO:0000256|RuleBase:RU003324}. CC -!- SUBUNIT: Homotrimer of disulfide-linked HA1-HA2. CC {ECO:0000256|RuleBase:RU003324, ECO:0000256|SAAS:SAAS00070616}. CC -!- SUBCELLULAR LOCATION: Host apical cell membrane CC {ECO:0000256|SAAS:SAAS00554492}; Single-pass type I membrane CC protein {ECO:0000256|SAAS:SAAS00554492}. CC -!- SUBCELLULAR LOCATION: Virion membrane CC {ECO:0000256|SAAS:SAAS00554193}; Single-pass type I membrane CC protein {ECO:0000256|SAAS:SAAS00554193}. CC -!- SIMILARITY: Belongs to the influenza viruses hemagglutinin family. CC {ECO:0000256|RuleBase:RU003324, ECO:0000256|SAAS:SAAS00554639}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; DQ336013; ABC66254.1; -; Genomic_RNA. DR GO; GO:0020002; C:host cell plasma membrane; IEA:UniProtKB-SubCell. DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW. DR GO; GO:0019031; C:viral envelope; IEA:UniProtKB-KW. DR GO; GO:0055036; C:virion membrane; IEA:UniProtKB-SubCell. DR GO; GO:0046789; F:host cell surface receptor binding; IEA:InterPro. DR GO; GO:0075512; P:clathrin-dependent endocytosis of virus by host cell; IEA:UniProtKB-KW. DR GO; GO:0039654; P:fusion of virus membrane with host endosome membrane; IEA:UniProtKB-KW. DR GO; GO:0019064; P:fusion of virus membrane with host plasma membrane; IEA:InterPro. DR GO; GO:0019062; P:virion attachment to host cell; IEA:UniProtKB-KW. DR Gene3D; 3.90.209.20; -; 1. DR InterPro; IPR008980; Capsid_hemagglutn. DR InterPro; IPR013828; Hemagglutn_HA1_a/b_dom_sf. DR InterPro; IPR000149; Hemagglutn_influenz_A. DR InterPro; IPR001364; Hemagglutn_influenz_A/B. DR Pfam; PF00509; Hemagglutinin; 1. DR PRINTS; PR00330; HEMAGGLUTN1. DR PRINTS; PR00329; HEMAGGLUTN12. DR SUPFAM; SSF49818; SSF49818; 1. PE 3: Inferred from homology; KW Clathrin- and caveolin-independent endocytosis of virus by host KW {ECO:0000256|SAAS:SAAS00452788}; KW Clathrin-mediated endocytosis of virus by host KW {ECO:0000256|SAAS:SAAS00453157}; KW Disulfide bond {ECO:0000256|SAAS:SAAS00442250}; KW Fusion of virus membrane with host endosomal membrane KW {ECO:0000256|SAAS:SAAS00046943}; KW Fusion of virus membrane with host membrane KW {ECO:0000256|SAAS:SAAS00046961}; KW Hemagglutinin {ECO:0000256|RuleBase:RU003324, KW ECO:0000256|SAAS:SAAS00046890}; KW Host cell membrane {ECO:0000256|SAAS:SAAS00047107}; KW Host membrane {ECO:0000256|SAAS:SAAS00047336}; KW Host-virus interaction {ECO:0000256|SAAS:SAAS00046894}; KW Membrane {ECO:0000256|SAAS:SAAS00047309}; KW Transmembrane {ECO:0000256|SAAS:SAAS00443026}; KW Transmembrane helix {ECO:0000256|SAAS:SAAS00441560}; KW Viral attachment to host cell {ECO:0000256|SAAS:SAAS00441705}; KW Viral envelope protein {ECO:0000256|RuleBase:RU003324, KW ECO:0000256|SAAS:SAAS00046987}; KW Viral penetration into host cytoplasm {ECO:0000256|SAAS:SAAS00046884}; KW Virion {ECO:0000256|SAAS:SAAS00070858}; KW Virus endocytosis by host {ECO:0000256|SAAS:SAAS00842033}; KW Virus entry into host cell {ECO:0000256|SAAS:SAAS00047696}. FT NON_TER 1 1 {ECO:0000313|EMBL:ABC66254.1}. FT NON_TER 328 328 {ECO:0000313|EMBL:ABC66254.1}. SQ SEQUENCE 328 AA; 36418 MW; D12F8FF466F912CC CRC64; QKLPGNDNST ATLCLGHHAV PNGTLVKTIT NDQIEVTNAT ELVQSSSTGR ICDSPHRILD GKNCTLIDAL LGDPHCDGFQ NKEWDLFVER SKAYSNCYPY DVPDYASLRS LVASSGTLEF INEDFNWTGV AQSGESYACK RGSVKSFFSR LNWLHKSDYK YPALNVTMPN NGKFDKLYIW GVHHPSTDRE QTSLYVRASG RVTVSTKRSQ QTVIPNIGSR PWVRGLSSRI SIYWTIVKPG DILLINSTGN LIAPRGYFKI RTGKSSIMRS DAPIGTCSSE CITPNGSIPN DKPFQNVNRI TYGACPRYVK QNTLKLATGM RNVPEKQN //