ID Q67045_9INFA Unreviewed; 131 AA. AC Q67045; DT 01-NOV-1996, integrated into UniProtKB/TrEMBL. DT 01-NOV-1996, sequence version 1. DT 20-DEC-2017, entry version 104. DE SubName: Full=Hemagglutinin {ECO:0000313|EMBL:BAA02771.1}; DE Flags: Fragment; GN Name=HA {ECO:0000313|EMBL:BAA02771.1}; OS Influenza A virus (A/Adachi/2/1957(H2N2)). OC Viruses; ssRNA viruses; ssRNA negative-strand viruses; OC Orthomyxoviridae; Influenzavirus A. OX NCBI_TaxID=516994 {ECO:0000313|EMBL:BAA02771.1}; RN [1] {ECO:0000313|EMBL:BAA02771.1} RP NUCLEOTIDE SEQUENCE. RC STRAIN=A/Adachi/2/57 {ECO:0000313|EMBL:BAA02771.1}; RX PubMed=7421990; DOI=10.1038/287301a0; RA Gething M.J., Bye J., Skehel J., Waterfield M.; RT "Cloning and DNA sequence of double-stranded copies of haemagglutinin RT genes from H2 and H3 strains elucidates antigenic shift and drift in RT human influenza virus."; RL Nature 287:301-306(1980). RN [2] {ECO:0000313|EMBL:BAA02771.1} RP NUCLEOTIDE SEQUENCE. RC STRAIN=A/Adachi/2/57 {ECO:0000313|EMBL:BAA02771.1}; RX PubMed=7682624; RA Okuno Y., Isegawa Y., Sasao F., Ueda S.; RT "A common neutralizing epitope conserved between the hemagglutinins of RT influenza A virus H1 and H2 strains."; RL J. Virol. 67:2552-2558(1993). 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}. CC -!- SUBCELLULAR LOCATION: Virion {ECO:0000256|SAAS:SAAS00562712}. CC -!- SIMILARITY: Belongs to the influenza viruses hemagglutinin family. CC {ECO:0000256|RuleBase:RU003324}. 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; D13576; BAA02771.1; -; Genomic_RNA. DR ProteinModelPortal; Q67045; -. 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:0075509; P:endocytosis involved in viral entry into 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 InterPro; IPR008980; Capsid_hemagglutn. DR InterPro; IPR001364; Hemagglutn_influenz_A/B. DR InterPro; IPR000386; Hemagglutn_influenz_B. DR Pfam; PF00509; Hemagglutinin; 1. DR PRINTS; PR00329; HEMAGGLUTN12. DR PRINTS; PR00331; HEMAGGLUTN2. DR SUPFAM; SSF49818; SSF49818; 1. PE 3: Inferred from homology; KW Coiled coil {ECO:0000256|SAM:Coils}; KW Hemagglutinin {ECO:0000256|RuleBase:RU003324}; KW Viral envelope protein {ECO:0000256|RuleBase:RU003324}; KW Virion {ECO:0000256|SAAS:SAAS00070858}. FT COILED 104 124 {ECO:0000256|SAM:Coils}. FT NON_TER 1 1 {ECO:0000313|EMBL:BAA02771.1}. FT NON_TER 131 131 {ECO:0000313|EMBL:BAA02771.1}. SQ SEQUENCE 131 AA; 14550 MW; 243DFC623E7F2952 CRC64; NTTLPFHNVH PLTIGECPKY VKSEKLVLAT GLRNVPQIES RGLFGAIAGF IEGGWQGMVD GWYGYHHSND QGSGYAADKE STQKAFDGIT NKVNSVIEKM NTQFEAVGKE FGNLERRLEN LNKKMEDGFL D //