Annotations: 9HJ9

H1-H3 chimeric hemagglutinin

External Resource: Annotation

Domain Annotation: ECOD Classification
SAbDab Antibody Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
C [auth D]	SPRY	e9hj9D1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: SPRY	ECOD (v295.2)
B [auth C]		e9hj9C1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F:	ECOD (v295.2)
A [auth B]	Peptidase_C1	e9hj9B1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: Peptidase_C1	ECOD (v295.2)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
C [auth D]	Light Chain	IGKV1	Kappa	hemagglutinin	SAbDab (2026-10-16)
B [auth C]	Heavy Chain	IGHV4	-	hemagglutinin	SAbDab (2026-10-16)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C [auth D]	FluA-20 fab light chain	-	-	-
B [auth C]	FluA-20 fab heavy chain	-	-	-
A [auth B]	Hemagglutinin	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 import into cell receptor-mediated endocytosis of virus by host cell biological process involved in interspecies interaction between organisms transport viral life cycle establishment of localization vesicle-mediated transport biological process involved in interaction with host biological process involved in symbiotic interaction localization symbiont entry into host cell viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell import into cell receptor-mediated endocytosis of virus by host cell biological process involved in interspecies interaction between organisms transport viral life cycle establishment of localization vesicle-mediated transport biological process involved in interaction with host biological process involved in symbiotic interaction localization symbiont entry into host cell clathrin-dependent endocytosis symbiont entry into host cellular process clathrin-dependent endocytosis of virus by host cell receptor-mediated endocytosis endocytosis endocytosis involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular component organization or biogenesis virion attachment to host cell adhesion of symbiont to host cell adhesion of symbiont to host	virion component viral membrane viral envelope host cell plasma membrane host cellular component cellular anatomical structure host cell part host cell membrane other organism part

InterPro: Protein Family Classification InterPro Database Homepage

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