Annotations: 3SPI

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	IRK_C	e3spiA1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: IRK_C	ECOD (1.6)
A	IRK_N	e3spiA2	A: alpha complex topology	X: Voltage-gated ion channels (From Topology)	H: Voltage-gated ion channels (From Topology)	T: Voltage-gated ion channels	F: IRK_N	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	2.60.40.1400	Mainly Beta	Sandwich	Immunoglobulin-like	G protein-activated inward rectifier potassium channel 1	CATH (4.3.0)
A	1.10.287.70	Mainly Alpha	Orthogonal Bundle	Helix Hairpins		CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF01007	Inward rectifier potassium channel transmembrane domain (IRK)	Inward rectifier potassium channel transmembrane domain	-	Domain
A	PF17655	Inward rectifier potassium channel C-terminal domain (IRK_C)	Inward rectifier potassium channel C-terminal domain	This cytoplasmic C-terminal domain has an Ig fold.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Inward-rectifier K+ channel Kir2.2	inward rectifier potassium channel activity monoatomic cation transmembrane transporter activity gated channel activity monoatomic ion channel activity potassium ion transmembrane transporter activity voltage-gated channel activity voltage-gated monoatomic ion channel activity potassium channel activity voltage-gated monoatomic cation channel activity ligand-gated channel activity ligand-gated monoatomic ion channel activity monoatomic cation channel activity passive transmembrane transporter activity voltage-gated potassium channel activity inorganic molecular entity transmembrane transporter activity inward rectifier potassium channel activity monoatomic cation transmembrane transporter activity gated channel activity monoatomic ion channel activity potassium ion transmembrane transporter activity voltage-gated channel activity voltage-gated monoatomic ion channel activity potassium channel activity voltage-gated monoatomic cation channel activity ligand-gated channel activity ligand-gated monoatomic ion channel activity monoatomic cation channel activity passive transmembrane transporter activity voltage-gated potassium channel activity inorganic molecular entity transmembrane transporter activity channel activity inorganic cation transmembrane transporter activity monoatomic ion transmembrane transporter activity transporter activity metal ion transmembrane transporter activity ligand-gated monoatomic cation channel activity transmembrane transporter activity identical protein binding protein binding binding	localization transport monoatomic ion transport potassium ion transport monoatomic cation transport establishment of localization metal ion transport regulation of localization regulation of biological process regulation of cellular process regulation of transport monoatomic ion transmembrane transport regulation of monoatomic ion transport biological regulation localization transport monoatomic ion transport potassium ion transport monoatomic cation transport establishment of localization metal ion transport regulation of localization regulation of biological process regulation of cellular process regulation of transport monoatomic ion transmembrane transport regulation of monoatomic ion transport biological regulation regulation of monoatomic ion transmembrane transport transmembrane transport regulation of transmembrane transport cellular process protein-containing complex organization protein homotetramerization cellular component organization cellular component biogenesis cellular component assembly protein complex oligomerization protein tetramerization protein-containing complex assembly protein homooligomerization cellular component organization or biogenesis import into cell import across plasma membrane potassium ion transmembrane transport inorganic ion transmembrane transport inorganic cation import across plasma membrane inorganic cation transmembrane transport monoatomic cation transmembrane transport inorganic ion import across plasma membrane potassium ion import across plasma membrane	membrane cellular anatomical entity cell periphery plasma membrane protein-containing complex transmembrane transporter complex membrane protein complex transporter complex monoatomic ion channel complex

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR041647	Inward rectifier potassium channel, C-terminal	Domain
A	IPR040445	Potassium channel, inwardly rectifying, transmembrane domain	Domain
A	IPR003272	Potassium channel, inwardly rectifying, Kir2.2	Family
A	IPR016449	Potassium channel, inwardly rectifying, Kir	Family
A	IPR014756	Immunoglobulin E-set	Homologous Superfamily
A	IPR013673	Potassium channel, inwardly rectifying, Kir, N-terminal	Domain
A	IPR013518	Potassium channel, inwardly rectifying, Kir, cytoplasmic	Homologous Superfamily

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 R01GM157729.