Annotations: 1QFU

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1qfua_	All beta proteins	Viral protein domain	Viral protein domain	Influenza hemagglutinin headpiece	Hemagglutinin	(Influenza A virus (A/X-31(H3N2)) ) [TaxId: 132504 ],	SCOPe (2.08)
B	d1qfub_	Coiled coil proteins	Stalk segment of viral fusion proteins	Influenza hemagglutinin (stalk)	Influenza hemagglutinin (stalk)	Influenza hemagglutinin (stalk)	(Influenza A virus (A/X-31(H3N2)) ) [TaxId: 132504 ],	SCOPe (2.08)
C [auth L]	d1qful1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	Immunoglobulin light chain kappa variable domain, VL-kappa	(Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
C [auth L]	d1qful2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	Immunoglobulin light chain kappa constant domain, CL-kappa	(Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
D [auth H]	d1qfuh1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	Immunoglobulin heavy chain variable domain, VH	(Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
D [auth H]	d1qfuh2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	Immunoglobulin heavy chain gamma constant domain 1, CH1-gamma	(Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
D [auth H]	d1qfuh3	Artifacts	Tags	Tags	Tags	N-terminal Tags	(Mus musculus ) [TaxId: 10090 ],	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	8087829	4002506	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	Influenza hemagglutinin domain-like	8087830	3001342	SCOP2 (2022-06-29)
B	SCOP2B Superfamily	Influenza hemagglutinin (stalk)	8088038	3001616	SCOP2B (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	e1qfuA1	A: beta sandwiches	X: jelly-roll	H: Viral protein domain (From Topology)	T: Viral protein domain	F: Hemagglutinin_1st	ECOD (1.6)
C [auth L]	C1-set_4	e1qfuL2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_4	ECOD (1.6)
D [auth H]	V-set_8	e1qfuH1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_8	ECOD (1.6)
D [auth H]	C1-set_1	e1qfuH2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_1	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.90.209.20	Alpha Beta	Alpha-Beta Complex	Hemagglutinin (Ha1 Chain)	Chain: A	CATH (4.3.0)
A	2.10.77.10	Mainly Beta	Ribbon	Hemagglutinin	Chain A, domain 2	CATH (4.3.0)
B	3.90.20.10	Alpha Beta	Alpha-Beta Complex	Hemagglutinin Ectodomain	Chain B	CATH (4.3.0)
C [auth L]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
D [auth H]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)

IMGT Antibody Annotation IMGT Database Homepage

Chain	Protein Name	Description	Organism Name	Gene Allele Name(s)	Domain Name(s)	Receptor Type	Receptor Description	Provenance Source
C [auth L]	Influenza hemagglutinin neutralizing Fab	L-KAPPA	Mus musculus (house mouse)	IGKV1-11001, IGKJ201, IGKC01, IGKC02	V-DOMAIN V-KAPPA, C-DOMAIN C-KAPPA	IG	FAB-GAMMA-1_KAPPA	IMGT (202506-0)
D [auth H]	Influenza hemagglutinin neutralizing Fab	VH-CH1	Mus musculus (house mouse)	IGHV1-5201, IGHJ401, IGHG1*02	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-1_KAPPA	IMGT (202506-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
C [auth L]	Light Chain	IGKV1	Kappa	protein (hemagglutinin (ha1 chain))	SAbDab (2025-02-21)
D [auth H]	Heavy Chain	IGHV1	-	protein (hemagglutinin (ha1 chain))	SAbDab (2025-02-21)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF00509	Haemagglutinin (Hemagglutinin)	Haemagglutinin	-	Family
B	PF00509	Haemagglutinin (Hemagglutinin)	Haemagglutinin	-	Family
C [auth L]	PF07686	Immunoglobulin V-set domain (V-set)	Immunoglobulin V-set domain	This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.	Domain
C [auth L]	PF07654	Immunoglobulin C1-set domain (C1-set)	Immunoglobulin C1-set domain		Domain
D [auth H]	PF07654	Immunoglobulin C1-set domain (C1-set)	Immunoglobulin C1-set domain		Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	PROTEIN (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 non-lytic viral release viral budding virion assembly exit from host cell viral budding from plasma membrane viral release from host cell 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	cellular anatomical structure membrane virion component virion membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane
B	PROTEIN (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 non-lytic viral release viral budding virion assembly exit from host cell viral budding from plasma membrane viral release from host cell 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	cellular anatomical structure membrane virion component virion membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane
C [auth L]	PROTEIN (IMMUNOGLOBULIN IGG1-KAPPA ANTIBODY (LIGHT CHAIN))	cation binding ion binding binding metal ion binding small molecule binding	-	-
D [auth H]	PROTEIN (IMMUNOGLOBULIN IGG1-KAPPA ANTIBODY (HEAVY CHAIN))	protein binding binding signaling receptor binding immunoglobulin receptor binding antigen binding	regulation of biological process response to stimulus immune response biological regulation positive regulation of biological process positive regulation of response to stimulus positive regulation of immune response regulation of response to stimulus immune system process regulation of immune response regulation of immune system process positive regulation of immune system process adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity regulation of biological process response to stimulus immune response biological regulation positive regulation of biological process positive regulation of response to stimulus positive regulation of immune response regulation of response to stimulus immune system process regulation of immune response regulation of immune system process positive regulation of immune system process adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity B cell mediated immunity leukocyte mediated immunity immunoglobulin mediated immune response adaptive immune response immune effector process membrane organization import into cell transport establishment of localization vesicle-mediated transport cellular component organization localization phagocytosis, engulfment membrane invagination cellular process phagocytosis cellular component organization or biogenesis endocytosis plasma membrane invagination positive regulation of acute inflammatory response to antigenic stimulus regulation of immune effector process regulation of acute inflammatory response to antigenic stimulus positive regulation of leukocyte mediated immunity inflammatory response to antigenic stimulus positive regulation of hypersensitivity positive regulation of inflammatory response positive regulation of adaptive immune response positive regulation of immunoglobulin mediated immune response hypersensitivity regulation of adaptive immune response response to external stimulus regulation of inflammatory response regulation of B cell mediated immunity regulation of leukocyte mediated immunity positive regulation of defense response regulation of acute inflammatory response inflammatory response positive regulation of type I hypersensitivity regulation of type I hypersensitivity regulation of defense response regulation of response to external stimulus positive regulation of adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains positive regulation of lymphocyte mediated immunity positive regulation of acute inflammatory response positive regulation of B cell mediated immunity type I hypersensitivity positive regulation of response to external stimulus regulation of adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains response to stress regulation of response to stress regulation of immunoglobulin mediated immune response positive regulation of immune effector process acute inflammatory response regulation of hypersensitivity defense response regulation of inflammatory response to antigenic stimulus acute inflammatory response to antigenic stimulus positive regulation of inflammatory response to antigenic stimulus regulation of lymphocyte mediated immunity myeloid leukocyte mediated immunity antibody-dependent cellular cytotoxicity leukocyte mediated cytotoxicity type II hypersensitivity type IIa hypersensitivity cell killing developmental process multicellular organismal process cellular developmental process hemopoiesis B cell activation cell activation cell development mononuclear cell differentiation lymphocyte differentiation lymphocyte activation leukocyte activation B cell differentiation cell differentiation anatomical structure development leukocyte differentiation regulation of myeloid leukocyte mediated immunity regulation of type IIa hypersensitivity regulation of type II hypersensitivity positive regulation of myeloid leukocyte mediated immunity positive regulation of type IIa hypersensitivity positive regulation of type II hypersensitivity humoral immune response complement activation humoral immune response mediated by circulating immunoglobulin complement activation, classical pathway activation of immune response biological process involved in interspecies interaction between organisms response to other organism antibacterial humoral response defense response to symbiont antimicrobial humoral response response to biotic stimulus defense response to bacterium defense response to other organism response to bacterium response to external biotic stimulus regulation of localization positive regulation of cellular component organization regulation of cellular process regulation of cellular component organization positive regulation of endocytosis positive regulation of cellular process regulation of endocytosis regulation of transport regulation of phagocytosis regulation of vesicle-mediated transport positive regulation of phagocytosis positive regulation of transport phagocytosis, recognition cell recognition	cell periphery cellular anatomical structure cell surface membrane plasma membrane external side of plasma membrane side of membrane protein-containing complex extracellular region extracellular space immunoglobulin complex, circulating immunoglobulin complex intracellular anatomical structure cytoplasm

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
C [auth L]	IPR003597	Immunoglobulin C1-set	Domain
C [auth L]	IPR050150	Immunoglobulin Variable Light Chain	Family
C [auth L]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
C [auth L]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
C [auth L]	IPR013106	Immunoglobulin V-set domain	Domain
C [auth L]	IPR003599	Immunoglobulin domain subtype	Domain
C [auth L]	IPR007110	Immunoglobulin-like domain	Domain
C [auth L]	IPR003006	Immunoglobulin/major histocompatibility complex, conserved site	Conserved Site
D [auth H]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
D [auth H]	IPR050380	Immune Recognition and Response Modulators	Family
D [auth H]	IPR003597	Immunoglobulin C1-set	Domain
D [auth H]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
D [auth H]	IPR007110	Immunoglobulin-like domain	Domain