9RXN: PDB entry 9RXN

Structure of the PDZ1 domain from human PDZK1 (NHERF3) with the C-terminal residues (KSTQF) of human URAT1 transporter (SLC22A12). Determined by X-ray diffraction at 1.36 Å resolution. Released 14 Jan 2026.

Method: X-ray diffraction
Resolution: 1.36 Å
Organism: Homo sapiens
Chains: 2
Atoms: 2,249
Mol. weight: 24.25 kDa
Released: 14 Jan 2026

Explore 9RXN in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9RXN contains 8 α-helices and 13 β-strands across 2 chains. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 4 helices, 6 β-strands

Element	Residues	Length	Sheet
β-strand	8-13	6	1
β-strand	23-25	3	1
β-strand	34-36	3	1
α-helix	43-47	5
β-strand	54-58	5	1
β-strand	61-62	2	1
α-helix	68-77	10
β-strand	81-87	7	1
α-helix	89-97	9
α-helix	102-104	3

Chain B: 4 helices, 7 β-strands

Element	Residues	Length	Sheet
β-strand	8-13	6	2
β-strand	23-25	3	2
β-strand	34-36	3	2
α-helix	43-47	5
β-strand	54-58	5	2
β-strand	61-62	2	2
α-helix	68-77	10
β-strand	81-87	7	2
α-helix	89-97	9
α-helix	102-104	3
β-strand	108-110	3	1

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Na(+)/H(+) exchange regulatory cofactor NHE-RF3,Solute carrier family 22 member 12	A, B	protein	107	Homo sapiens	Q5T2W1 (AlphaFold model)

Sequence of entity 1 (A, B), FASTA

>9RXN_1 Na(+)/H(+) exchange regulatory cofactor NHE-RF3,Solute carrier family 22 member 12 (chains A, B)
GNPRECKLSKQEGQNYGFFLRIEKDTEGHLVRVVEKCSPAEKAGLQDGDRVLRINGVFVD
KEEHMQVVDLVRKSGNSVTLLVLDGDSYEKAVKTRVDLKELGKSTQF

Primary citation

Molecular Determinants of Selective and High-affinity Binding of the Scaffold Protein PDZK1 to the Urate Transporter URAT1. Mymrikov, E.V., Wirth, C., Heinicke, J.I. et al. J Mol Biol (2025) 438:169615-169615. DOI 10.1016/j.jmb.2025.169615 · PubMed

Other PDB entries of the same protein (UniProt Q5T2W1 (AlphaFold model), which also has an AlphaFold model), best resolution first:

9RXO 1.2 Å, Structure of the PDZ2 domain from human PDZK1 (NHERF3) with the C-terminal residues…
9RXP 1.43 Å, Structure of the PDZ4 domain from human PDZK1 (NHERF3) with the C-terminal residues…
6EZI 1.5 Å, PDZK1 domain 4 in complex with C-terminal peptide of human PepT2.
9RXR 1.69 Å, Structure of the PDZ1 domain from human PDZK1 (NHERF3) with the C-terminal residues…
9RXS 2.0 Å, Structure of the PDZ4 domain from human PDZK1 (NHERF3) with the C-terminal residues…
4Q2P 2.05 Å, NHERF3 PDZ2 in Complex with a Phage-Derived Peptide
2VSP 2.41 Å, Crystal structure of the fourth PDZ domain of PDZ domain-containing protein 1
3TMH 3.8 Å, Crystal structure of dual-specific A-kinase anchoring protein 2 in complex with…
2EEI Solution Structure of Second PDZ domain of PDZ Domain Containing Protein 1
2EEJ Solution Structure of Fourth PDZ domain of PDZ Domain Containing Protein 1

Browse structure collections

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