9RXS: PDB entry 9RXS

Structure of the PDZ4 domain from human PDZK1 (NHERF3) with the C-terminal residues (VLKSTQF) of human URAT1 transporter (SLC22A12). Determined by X-ray diffraction at 2.0 Å resolution. Released 14 Jan 2026.

Method: X-ray diffraction
Resolution: 2.0 Å
Organism: Homo sapiens
Chains: 2
Atoms: 1,546
Mol. weight: 19.94 kDa
Released: 14 Jan 2026

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

Secondary structure: helices and β-sheets

9RXS contains 5 α-helices and 15 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: 3 helices, 8 β-strands

Element	Residues	Length	Sheet
β-strand	377-382	6	1
β-strand	384	1	2
β-strand	387	1	2
β-strand	391-393	3	1
β-strand	402-404	3	1
α-helix	406-407	2
α-helix	411-414	4
β-strand	422-426	5	1
β-strand	429-430	2	1
α-helix	436-445	10
β-strand	449-455	7	1

Chain B: 2 helices, 7 β-strands

Element	Residues	Length	Sheet
β-strand	376-382	7	3
β-strand	384-388	5	4
β-strand	391-393	3	3
β-strand	402-404	3	3
α-helix	411-415	5
β-strand	422-426	5	3
β-strand	429-430	2	3
α-helix	436-446	11
β-strand	449-455	7	3

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	92	Homo sapiens	Q5T2W1 (AlphaFold model), Q96S37 (AlphaFold model)

Sequence of entity 1 (A, B), FASTA

>9RXS_1 Na(+)/H(+) exchange regulatory cofactor NHE-RF3,Solute carrier family 22 member 12 (chains A, B)
GKPKLCRLAKGENGYGFHLNAIRGLPGSFIKEVQKGGPADLAGLEDEDVIIEVNGVNVLD
EPYEKVVDRIQSSGKNVTLLVCGKKVLKSTQF

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…
9RXN 1.36 Å, Structure of the PDZ1 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…
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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