Annotations: 7NP3

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	PF00027	e7np3A2	A: beta sandwiches	X: jelly-roll	H: Double-stranded beta-helix (From Topology)	T: Double-stranded beta-helix	F: PF00027	ECOD (1.6)
A	PF00520,PF08412	e7np3A1	A: alpha complex topology	X: Voltage-gated ion channels (From Topology)	H: Voltage-gated ion channels (From Topology)	T: Voltage-gated ion channels	F: PF00520,PF08412	ECOD (1.6)
B	PF00027	e7np3B2	A: beta sandwiches	X: jelly-roll	H: Double-stranded beta-helix (From Topology)	T: Double-stranded beta-helix	F: PF00027	ECOD (1.6)
B	PF00520,PF08412	e7np3B1	A: alpha complex topology	X: Voltage-gated ion channels (From Topology)	H: Voltage-gated ion channels (From Topology)	T: Voltage-gated ion channels	F: PF00520,PF08412	ECOD (1.6)
C	PF00027	e7np3C2	A: beta sandwiches	X: jelly-roll	H: Double-stranded beta-helix (From Topology)	T: Double-stranded beta-helix	F: PF00027	ECOD (1.6)
C	PF00520,PF08412	e7np3C1	A: alpha complex topology	X: Voltage-gated ion channels (From Topology)	H: Voltage-gated ion channels (From Topology)	T: Voltage-gated ion channels	F: PF00520,PF08412	ECOD (1.6)
D	PF00027	e7np3D2	A: beta sandwiches	X: jelly-roll	H: Double-stranded beta-helix (From Topology)	T: Double-stranded beta-helix	F: PF00027	ECOD (1.6)
D	PF00520,PF08412	e7np3D1	A: alpha complex topology	X: Voltage-gated ion channels (From Topology)	H: Voltage-gated ion channels (From Topology)	T: Voltage-gated ion channels	F: PF00520,PF08412	ECOD (1.6)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B, C, D	PF08412	Ion transport protein N-terminal (Ion_trans_N)	Ion transport protein N-terminal	-	Family
A, B, C, D	PF00520	Ion transport protein (Ion_trans)	Ion transport protein	-	Family
A, B, C, D	PF00027	Cyclic nucleotide-binding domain (cNMP_binding)	Cyclic nucleotide-binding domain	This domain sensor domain can bind cAMP, cGMP, c-di-GMP, oxygen and 2-oxoglutarate (Matilla et. al., FEMS Microbiology Reviews, fuab043, 45, 2021, 1. https://doi.org/10.1093/femsre/fuab043).	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B, C, D	Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 4,Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 4	monoatomic cation transmembrane transporter activity intracellularly ligand-gated monoatomic ion channel activity gated channel activity monoatomic ion channel activity intracellularly cyclic nucleotide-activated monoatomic cation channel activity ligand-gated channel activity ligand-gated monoatomic ion channel activity monoatomic cation channel activity intracellularly cAMP-activated cation channel activity passive transmembrane transporter activity channel activity monoatomic ion transmembrane transporter activity transporter activity ligand-gated monoatomic cation channel activity cyclic nucleotide-activated monoatomic ion channel activity monoatomic cation transmembrane transporter activity intracellularly ligand-gated monoatomic ion channel activity gated channel activity monoatomic ion channel activity intracellularly cyclic nucleotide-activated monoatomic cation channel activity ligand-gated channel activity ligand-gated monoatomic ion channel activity monoatomic cation channel activity intracellularly cAMP-activated cation channel activity passive transmembrane transporter activity channel activity monoatomic ion transmembrane transporter activity transporter activity ligand-gated monoatomic cation channel activity cyclic nucleotide-activated monoatomic ion channel activity transmembrane transporter activity binding adenyl ribonucleotide binding cyclic nucleotide binding nucleotide binding purine ribonucleotide binding nucleoside phosphate binding ion binding purine nucleotide binding organic cyclic compound binding anion binding cAMP binding adenyl nucleotide binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding small molecule binding sodium channel activity sodium ion transmembrane transporter activity inorganic molecular entity transmembrane transporter activity inorganic cation transmembrane transporter activity metal ion transmembrane transporter 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 voltage-gated potassium channel activity	heart process multicellular organismal process system process regulation of biological process regulation of heart contraction regulation of system process biological regulation circulatory system process regulation of blood circulation regulation of multicellular organismal process regulation of biological quality heart contraction blood circulation regulation of heart rate heart process multicellular organismal process system process regulation of biological process regulation of heart contraction regulation of system process biological regulation circulatory system process regulation of blood circulation regulation of multicellular organismal process regulation of biological quality heart contraction blood circulation regulation of heart rate transport monoatomic ion transmembrane transport potassium ion transmembrane transport inorganic ion transmembrane transport establishment of localization metal ion transport inorganic cation transmembrane transport transmembrane transport monoatomic cation transmembrane transport localization monoatomic ion transport potassium ion transport cellular process monoatomic cation transport cellular response to stimulus cellular response to nitrogen compound response to organic substance response to stimulus response to organonitrogen compound response to endogenous stimulus response to organophosphorus cellular response to organic cyclic compound response to oxygen-containing compound response to nitrogen compound response to purine-containing compound response to cAMP cellular response to oxygen-containing compound cellular response to endogenous stimulus cellular response to chemical stimulus cellular response to organonitrogen compound response to chemical cellular response to cAMP cellular response to organic substance response to organic cyclic compound	cell periphery plasma membrane membrane cellular anatomical entity 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, B, C, D	IPR005821	Ion transport domain	Domain
A, B, C, D	IPR003938	Potassium channel, voltage-dependent, EAG/ELK/ERG	Family
A, B, C, D	IPR000595	Cyclic nucleotide-binding domain	Domain
A, B, C, D	IPR013621	Ion transport N-terminal	Domain
A, B, C, D	IPR014710	RmlC-like jelly roll fold	Homologous Superfamily
A, B, C, D	IPR018488	Cyclic nucleotide-binding, conserved site	Conserved Site
A, B, C, D	IPR018490	Cyclic nucleotide-binding domain superfamily	Homologous Superfamily

Membrane Protein Annotation: OPM OPM Database Homepage

Chains	External Link	Type	Class	Superfamily	Family
A, B, C, D	OPM	Transmembrane	Alpha-helical polytopic	Ion channel (VIC) superfamily	Cyclic nucleotide-gated ion channel

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A, B, C, D	PDBTM	Annotated as membrane protein by PDBTM

Membrane Protein Annotation: MemProtMD MemProtMD Database Homepage

Chains	External Link	Comment
A, B, C, D	MemProtMD	Annotated as membrane protein by MemProtMD

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A, B, C, D	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	Channels: Potassium, Sodium, & Proton Ion-Selective	HCN4 hyperpolarization-activated channel stabilised in amphipol A8-35

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.