1U4F

Crystal Structure of Cytoplasmic Domains of IRK1 (Kir2.1) channel

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1u4fa_	All beta proteins	Immunoglobulin-like beta-sandwich	E set domains	Cytoplasmic domain of inward rectifier potassium channel	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ], house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
B	d1u4fb_	All beta proteins	Immunoglobulin-like beta-sandwich	E set domains	Cytoplasmic domain of inward rectifier potassium channel	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ], house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
C	d1u4fc_	All beta proteins	Immunoglobulin-like beta-sandwich	E set domains	Cytoplasmic domain of inward rectifier potassium channel	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ], house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
D	d1u4fd_	All beta proteins	Immunoglobulin-like beta-sandwich	E set domains	Cytoplasmic domain of inward rectifier potassium channel	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ], house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	IRK_C	e1u4fA1	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)
B	IRK_C	e1u4fB1	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)
C	IRK_C	e1u4fC1	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)
D	IRK_C	e1u4fD1	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)

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)
B	2.60.40.1400	Mainly Beta	Sandwich	Immunoglobulin-like	G protein-activated inward rectifier potassium channel 1	CATH (4.3.0)
C	2.60.40.1400	Mainly Beta	Sandwich	Immunoglobulin-like	G protein-activated inward rectifier potassium channel 1	CATH (4.3.0)
D	2.60.40.1400	Mainly Beta	Sandwich	Immunoglobulin-like	G protein-activated inward rectifier potassium channel 1	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B, C, D	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, B, C, D	Inward rectifier potassium channel 2	binding ion binding phosphatidylinositol-4,5-bisphosphate binding anion binding phosphatidylinositol bisphosphate binding phospholipid binding lipid binding phosphatidylinositol phosphate binding phosphatidylinositol binding small molecule binding inward rectifier potassium channel activity monoatomic cation transmembrane transporter activity gated channel activity monoatomic ion channel activity binding ion binding phosphatidylinositol-4,5-bisphosphate binding anion binding phosphatidylinositol bisphosphate binding phospholipid binding lipid binding phosphatidylinositol phosphate binding phosphatidylinositol binding small molecule binding 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 voltage-gated potassium channel activity involved in cardiac muscle cell action potential repolarization identical protein binding protein binding	heart process multicellular organismal process system process regulation of actin filament-based process regulation of cellular process regulation of heart contraction regulation of system process cardiac muscle contraction striated muscle contraction circulatory system process actin filament-based process regulation of multicellular organismal process blood circulation cardiac muscle cell contraction heart process multicellular organismal process system process regulation of actin filament-based process regulation of cellular process regulation of heart contraction regulation of system process cardiac muscle contraction striated muscle contraction circulatory system process actin filament-based process regulation of multicellular organismal process blood circulation cardiac muscle cell contraction regulation of biological process biological regulation regulation of cardiac muscle contraction actin filament-based movement muscle contraction muscle system process regulation of muscle system process regulation of blood circulation regulation of striated muscle contraction regulation of actin filament-based movement regulation of muscle contraction regulation of cardiac muscle cell contraction cellular process actin-mediated cell contraction heart contraction relaxation of cardiac muscle relaxation of muscle cardiac muscle cell action potential involved in contraction action potential regulation of biological quality cardiac muscle cell action potential regulation of membrane potential membrane repolarization regulation of membrane repolarization 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 localization transport monoatomic ion transport potassium ion transport monoatomic cation transport establishment of localization metal ion transport cellular response to stimulus response to stimulus response to mechanical stimulus response to external stimulus response to abiotic stimulus cellular response to mechanical stimulus cellular response to abiotic stimulus cellular response to external stimulus cellular response to environmental stimulus regulation of localization regulation of transport monoatomic ion transmembrane transport regulation of monoatomic ion transport regulation of monoatomic ion transmembrane transport transmembrane transport regulation of transmembrane transport relaxation of skeletal muscle magnesium ion transport 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 multicellular organismal movement musculoskeletal movement regulation of skeletal muscle contraction by action potential regulation of skeletal muscle contraction regulation of action potential nervous system process neuromuscular process skeletal muscle contraction regulation of skeletal muscle contraction via regulation of action potential positive regulation of cation transmembrane transport regulation of potassium ion transport positive regulation of biological process positive regulation of monoatomic ion transport positive regulation of transmembrane transport positive regulation of monoatomic ion transmembrane transport regulation of metal ion transport positive regulation of cellular process regulation of potassium ion transmembrane transport positive regulation of potassium ion transport positive regulation of transport positive regulation of potassium ion transmembrane transport regulation of monoatomic cation transmembrane transport cardiac conduction regulation of heart rate by cardiac conduction regulation of heart rate	cell periphery postsynapse postsynaptic membrane synapse cell junction membrane plasma membrane plasma membrane region cellular anatomical entity synaptic membrane sarcolemma T-tubule somatodendritic compartment cell projection cell periphery postsynapse postsynaptic membrane synapse cell junction membrane plasma membrane plasma membrane region cellular anatomical entity synaptic membrane sarcolemma T-tubule somatodendritic compartment cell projection dendrite dendritic tree neuron projection plasma membrane bounded cell projection glutamatergic synapse voltage-gated potassium channel complex protein-containing complex plasma membrane protein complex potassium channel complex membrane protein complex cation channel complex transporter complex transmembrane transporter complex monoatomic ion channel complex neuron spine dendritic spine cell body neuronal cell body cell-cell junction intercalated disc anchoring junction cell-cell contact zone

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B, C, D	IPR041647	Inward rectifier potassium channel, C-terminal	Domain
A, B, C, D	IPR040445	Potassium channel, inwardly rectifying, transmembrane domain	Domain
A, B, C, D	IPR016449	Potassium channel, inwardly rectifying, Kir	Family
A, B, C, D	IPR014756	Immunoglobulin E-set	Homologous Superfamily
A, B, C, D	IPR003271	Potassium channel, inwardly rectifying, Kir2.1	Family
A, B, C, D	IPR013673	Potassium channel, inwardly rectifying, Kir, N-terminal	Domain
A, B, C, D	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 R01GM133198.