Annotations: 8QH0

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF09408	Betacoronavirus spike glycoprotein S1, receptor binding (bCoV_S1_RBD)	Betacoronavirus spike glycoprotein S1, receptor binding	This entry represents the receptor binding domain (S1 RBD) of the betacoronavirus spike glycoprotein. The spike glycoprotein is arranged in trimers on the surface of the viral membrane and is essential for viral entry. The spike protein is transla ...	This entry represents the receptor binding domain (S1 RBD) of the betacoronavirus spike glycoprotein. The spike glycoprotein is arranged in trimers on the surface of the viral membrane and is essential for viral entry. The spike protein is translated as a large polypeptide that is subsequently cleaved to the distal S1, responsible for receptor binding, and the membrane-anchored S2 responsible for membrane fusion [1]. The coronavirus (SARS-CoV) S1 subunit is composed of two distinct domains: an N-terminal domain (S1 NTD) and a receptor-binding domain (S1 RBD) also referred to as the S1 CTD or domain B. Each of these domains have been implicated in binding to host receptors. However, most coronaviruses are not known to utilise both the S1 NTD and S1 RBD for viral entry [2]. SARS-CoV makes use of its S1 RBD to bind to the human angiotensin-converting enzyme 2 (ACE2) as its host receptor [3,4].	Domain
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

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Spike protein S1	protein binding binding molecular function activator activity signaling receptor binding molecular function regulator activity signaling receptor regulator activity receptor ligand activity signaling receptor activator activity host cell surface binding host cell surface receptor binding structural constituent of virion structural molecule activity identical protein 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 cellular process cellular component organization or biogenesis 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 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 cellular process cellular component organization or biogenesis 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 biological process involved in interaction with host vesicle-mediated transport biological process involved in symbiotic interaction localization symbiont entry into host cell symbiont entry into host endocytosis involved in viral entry into host cell endocytosis receptor-mediated endocytosis transport of virus symbiont-mediated perturbation of host defense response suppression by virus of host tetherin activity response to host defenses response to stimulus response to other organism response to defenses of other organism modulation by virus of host process response to external stimulus virus-mediated perturbation of host defense response response to biotic stimulus modulation by symbiont of host process response to host response to external biotic stimulus modulation of process of another organism modulation by virus of host cellular process virion attachment to host cell receptor-mediated virion attachment to host cell adhesion of symbiont to host cell adhesion of symbiont to host viral gene expression viral translation fusion of virus membrane with host plasma membrane regulation of biological process positive regulation of viral life cycle positive regulation of viral process biological regulation positive regulation of biological process modulation by symbiont of entry into host regulation of viral entry into host cell regulation of viral life cycle regulation of viral process positive regulation of viral entry into host cell positive regulation by symbiont of entry into host regulation of biological process involved in symbiotic interaction entry receptor-mediated virion attachment to host cell	membrane cellular anatomical entity host extracellular space host cellular component cell periphery plasma membrane host intracellular membrane-bounded organelle host intracellular part host cell membrane host cell cytoplasm part host intracellular organelle host cell endoplasmic reticulum-Golgi intermediate compartment membrane host cell endoplasmic reticulum-Golgi intermediate compartment host cell cytoplasm membrane cellular anatomical entity host extracellular space host cellular component cell periphery plasma membrane host intracellular membrane-bounded organelle host intracellular part host cell membrane host cell cytoplasm part host intracellular organelle host cell endoplasmic reticulum-Golgi intermediate compartment membrane host cell endoplasmic reticulum-Golgi intermediate compartment host cell cytoplasm host cell part host intracellular region host cell plasma membrane virion component virion membrane viral membrane viral envelope host cell surface
B [auth H]	Cv2.3194 Heavy chain	-	-	-
C [auth L]	IGK@ protein	-	response to stimulus immune response immune system process	extracellular region extracellular space cellular anatomical entity

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR044873	Spike glycoprotein S2, coronavirus, heptad repeat 1	Domain
A	IPR044366	Spike (S) protein S1 subunit, receptor-binding domain, SARS-CoV-2	Domain
A	IPR018548	Spike (S) protein S1 subunit, receptor-binding domain, betacoronavirus	Domain
A	IPR044341	Spike (S) protein S1 subunit, N-terminal domain, SARS-CoV-like	Domain
A	IPR032500	Spike glycoprotein S1, N-terminal domain, betacoronavirus-like	Domain
A	IPR042578	Spike glycoprotein, betacoronavirus	Family
A	IPR036326	Spike S1 subunit, receptor binding domain superfamily, betacoronavirus	Homologous Superfamily
A	IPR043002	Spike glycoprotein, N-terminal domain superfamily	Homologous Superfamily
A	IPR044874	Spike glycoprotein S2, coronavirus, heptad repeat 2	Domain
A	IPR043473	Spike glycoprotein S2 superfamily, coronavirus	Homologous Superfamily
A	IPR043607	Coronavirus spike glycoprotein S1, C-terminal	Domain
A	IPR002552	Spike glycoprotein S2, coronavirus	Domain
C [auth L]	IPR003597	Immunoglobulin C1-set	Domain
C [auth L]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
C [auth L]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
C [auth L]	IPR003599	Immunoglobulin subtype	Domain
C [auth L]	IPR013106	Immunoglobulin V-set domain	Domain
C [auth L]	IPR007110	Immunoglobulin-like domain	Domain
C [auth L]	IPR003006	Immunoglobulin/major histocompatibility complex, conserved site	Conserved Site

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), 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.