Annotations: 3S12

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d3s12a1	All beta proteins	Viral protein domain	Viral protein domain	Influenza hemagglutinin headpiece	Hemagglutinin	(Influenza A virus (A/chicken/Hong Kong/YU562/2001(H5N1)) ) [TaxId: 196426 ],	SCOPe (2.08)
A	d3s12a2	Artifacts	Tags	Tags	Tags	N-terminal Tags	(Influenza A virus (A/chicken/Hong Kong/YU562/2001(H5N1)) ) [TaxId: 196426 ],	SCOPe (2.08)
B	d3s12b_	Coiled coil proteins	Stalk segment of viral fusion proteins	Influenza hemagglutinin (stalk)	Influenza hemagglutinin (stalk)	Influenza hemagglutinin (stalk)	(Influenza A virus (A/chicken/Hong Kong/YU562/2001(H5N1)) ) [TaxId: 196426 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2 Family	Influenza hemagglutinin headpiece	8087751	4002506	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	Influenza hemagglutinin domain-like	8087752	3001342	SCOP2 (2022-06-29)
B	SCOP2 Family	Influenza hemagglutinin (stalk)	8087993	4003840	SCOP2 (2022-06-29)
B	SCOP2 Superfamily	Influenza hemagglutinin (stalk)	8087994	3001616	SCOP2 (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	Hemagglutinin_1st	e3s12A1	A: beta sandwiches	X: jelly-roll	H: Viral protein domain (From Topology)	T: Viral protein domain	F: Hemagglutinin_1st	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	2.10.77.10	Mainly Beta	Ribbon	Hemagglutinin	Chain A, domain 2	CATH (4.3.0)
A	3.90.209.20	Alpha Beta	Alpha-Beta Complex	Hemagglutinin (Ha1 Chain)	Chain: A	CATH (4.3.0)
B	3.90.20.10	Alpha Beta	Alpha-Beta Complex	Hemagglutinin Ectodomain	Chain B	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF00509	Haemagglutinin (Hemagglutinin)	Haemagglutinin	-	Family
B	PF00509	Haemagglutinin (Hemagglutinin)	Haemagglutinin	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Hemagglutinin HA1 chain	host cell surface binding binding host cell surface receptor binding	viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host biological process involved in interaction with host biological process involved in symbiotic interaction import into cell receptor-mediated endocytosis of virus by host cell transport establishment of localization vesicle-mediated transport localization symbiont entry into host cell clathrin-dependent endocytosis symbiont entry into host clathrin-dependent endocytosis of virus by host cell receptor-mediated endocytosis endocytosis endocytosis involved in viral entry into host cell transport of virus	membrane cellular anatomical entity virion component virion membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane
B	Hemagglutinin HA2 chain	host cell surface binding binding host cell surface receptor binding	viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host biological process involved in interaction with host biological process involved in symbiotic interaction import into cell receptor-mediated endocytosis of virus by host cell transport establishment of localization vesicle-mediated transport localization symbiont entry into host cell clathrin-dependent endocytosis symbiont entry into host clathrin-dependent endocytosis of virus by host cell receptor-mediated endocytosis endocytosis endocytosis involved in viral entry into host cell transport of virus	membrane cellular anatomical entity virion component virion membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR001364	Haemagglutinin, influenzavirus A/B	Family
A	IPR008980	Viral capsid/haemagglutinin protein	Homologous Superfamily
A	IPR000149	Haemagglutinin, influenzavirus A	Family
A	IPR013828	Haemagglutinin, HA1 chain, alpha/beta domain superfamily	Homologous Superfamily
B	IPR001364	Haemagglutinin, influenzavirus A/B	Family
B	IPR008980	Viral capsid/haemagglutinin protein	Homologous Superfamily
B	IPR000149	Haemagglutinin, influenzavirus A	Family
B	IPR013828	Haemagglutinin, HA1 chain, alpha/beta domain superfamily	Homologous Superfamily

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.