Annotations: 4J91

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Potassium channel/Rex NAD-binding domain-like	8057613	3000042	SCOP2B (2022-06-29)
B	SCOP2B Superfamily	Potassium channel/Rex NAD-binding domain-like	8057613	3000042	SCOP2B (2022-06-29)
C	SCOP2B Superfamily	Potassium channel/Rex NAD-binding domain-like	8057613	3000042	SCOP2B (2022-06-29)
D	SCOP2B Superfamily	Potassium channel/Rex NAD-binding domain-like	8057613	3000042	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	TrkA_C	e4j91A4	A: a+b two layers	X: TrkA C-terminal domain-like (From Topology)	H: TrkA C-terminal domain-like (From Topology)	T: TrkA C-terminal domain-like	F: TrkA_C	ECOD (1.6)
A	TrkA_N	e4j91A3	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: NAD(P)-binding Rossmann-fold domains	F: TrkA_N	ECOD (1.6)
B	TrkA_C	e4j91B4	A: a+b two layers	X: TrkA C-terminal domain-like (From Topology)	H: TrkA C-terminal domain-like (From Topology)	T: TrkA C-terminal domain-like	F: TrkA_C	ECOD (1.6)
B	TrkA_N	e4j91B3	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: NAD(P)-binding Rossmann-fold domains	F: TrkA_N	ECOD (1.6)
C	TrkA_C	e4j91C4	A: a+b two layers	X: TrkA C-terminal domain-like (From Topology)	H: TrkA C-terminal domain-like (From Topology)	T: TrkA C-terminal domain-like	F: TrkA_C	ECOD (1.6)
C	TrkA_N	e4j91C3	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: NAD(P)-binding Rossmann-fold domains	F: TrkA_N	ECOD (1.6)
D	TrkA_C	e4j91D4	A: a+b two layers	X: TrkA C-terminal domain-like (From Topology)	H: TrkA C-terminal domain-like (From Topology)	T: TrkA C-terminal domain-like	F: TrkA_C	ECOD (1.6)
D	TrkA_N	e4j91D3	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: NAD(P)-binding Rossmann-fold domains	F: TrkA_N	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.40.50.720	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NAD(P)-binding Rossmann-like Domain	CATH (4.3.0)
A	3.30.70.1450	Alpha Beta	2-Layer Sandwich	Alpha-Beta Plaits	Regulator of K+ conductance, C-terminal domain	CATH (4.3.0)
B	3.40.50.720	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NAD(P)-binding Rossmann-like Domain	CATH (4.3.0)
B	3.30.70.1450	Alpha Beta	2-Layer Sandwich	Alpha-Beta Plaits	Regulator of K+ conductance, C-terminal domain	CATH (4.3.0)
C	3.40.50.720	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NAD(P)-binding Rossmann-like Domain	CATH (4.3.0)
C	3.30.70.1450	Alpha Beta	2-Layer Sandwich	Alpha-Beta Plaits	Regulator of K+ conductance, C-terminal domain	CATH (4.3.0)
D	3.40.50.720	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NAD(P)-binding Rossmann-like Domain	CATH (4.3.0)
D	3.30.70.1450	Alpha Beta	2-Layer Sandwich	Alpha-Beta Plaits	Regulator of K+ conductance, C-terminal domain	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B, C, D	PF02080	TrkA-C domain (TrkA_C)	TrkA-C domain	This domain is often found next to the Pfam:PF02254 domain. The exact function of this domain is unknown. It has been suggested that it may bind an unidentified ligand [1]. The domain is predicted to adopt an all beta structure [1].	Domain
A, B, C, D	PF02254	TrkA-N domain (TrkA_N)	TrkA-N domain	This domain is found in a wide variety of proteins. These protein include potassium channels Swiss:P31069, phosphoesterases Swiss:Q59027, and various other transporters. This domain binds to NAD.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B, C, D	Ktr system potassium uptake protein A	monoatomic cation transmembrane transporter activity monoatomic ion transmembrane transporter activity transporter 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	cell periphery plasma membrane membrane cellular anatomical entity

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B, C, D	IPR006037	Regulator of K+ conductance, C-terminal	Domain
A, B, C, D	IPR050721	Trk/Ktr/HKT Potassium Transport	Family
A, B, C, D	IPR036291	NAD(P)-binding domain superfamily	Homologous Superfamily
A, B, C, D	IPR036721	Regulator of K+ conductance, C-terminal domain superfamily	Homologous Superfamily
A, B, C, D	IPR003148	Regulator of K+ conductance, N-terminal	Domain

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A, B, C, D	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	Superfamily of K⁺ Transporters (SKT proteins)	KtrAB potassium ion transporter

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.