Ovine rBAT ectodomain homodimer, asymmetric unit

  • Classification: TRANSLOCASE
  • Organism(s): Ovis aries
  • Expression System: Homo sapiens
  • Mutation(s): No 

  • Deposited: 2021-02-05 Released: 2022-01-19 
  • Deposition Author(s): Lee, Y., Kuehlbrandt, W.
  • Funding Organization(s): Max Planck Society, Human Frontier Science Program (HFSP)

Experimental Data Snapshot

  • Resolution: 2.68 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report

This is version 1.1 of the entry. See complete history


Ca 2+ -mediated higher-order assembly of heterodimers in amino acid transport system b 0,+ biogenesis and cystinuria.

Lee, Y.Wiriyasermkul, P.Kongpracha, P.Moriyama, S.Mills, D.J.Kuhlbrandt, W.Nagamori, S.

(2022) Nat Commun 13: 2708-2708

  • DOI: https://doi.org/10.1038/s41467-022-30293-9
  • Primary Citation of Related Structures:  
    7NF6, 7NF7, 7NF8

  • PubMed Abstract: 

    Cystinuria is a genetic disorder characterized by overexcretion of dibasic amino acids and cystine, causing recurrent kidney stones and kidney failure. Mutations of the regulatory glycoprotein rBAT and the amino acid transporter b 0,+ AT, which constitute system b 0,+ , are linked to type I and non-type I cystinuria respectively and they exhibit distinct phenotypes due to protein trafficking defects or catalytic inactivation. Here, using electron cryo-microscopy and biochemistry, we discover that Ca 2+ mediates higher-order assembly of system b 0,+ . Ca 2+ stabilizes the interface between two rBAT molecules, leading to super-dimerization of b 0,+ AT-rBAT, which in turn facilitates N-glycan maturation and protein trafficking. A cystinuria mutant T216M and mutations of the Ca 2+ site of rBAT cause the loss of higher-order assemblies, resulting in protein trapping at the ER and the loss of function. These results provide the molecular basis of system b 0,+ biogenesis and type I cystinuria and serve as a guide to develop new therapeutic strategies against it. More broadly, our findings reveal an unprecedented link between transporter oligomeric assembly and protein-trafficking diseases.

  • Organizational Affiliation

    Department of Structural Biology, Max Planck Institute of Biophysics, 60438, Frankfurt, Germany. yongchan.lee@biophys.mpg.de.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
neutral and basic amino acid transport protein rBAT686Ovis ariesMutation(s): 0 
Gene Names: SLC3A1
Find proteins for W5P8K2 (Ovis aries)
Explore W5P8K2 
Go to UniProtKB:  W5P8K2
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupW5P8K2
Glycosylation Sites: 6
Sequence Annotations
  • Reference Sequence


Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
B, C
Glycosylation Resources
GlyTouCan:  G42666HT
GlyCosmos:  G42666HT
GlyGen:  G42666HT
Experimental Data & Validation

Experimental Data

  • Resolution: 2.68 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report

Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
Max Planck SocietyGermany--
Human Frontier Science Program (HFSP)--

Revision History  (Full details and data files)

  • Version 1.0: 2022-01-19
    Type: Initial release
  • Version 1.1: 2022-06-01
    Changes: Database references, Derived calculations