4M90

crystal structure of oxidized hN33/Tusc3


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.186 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structural basis of substrate specificity of human oligosaccharyl transferase subunit n33/tusc3 and its role in regulating protein N-glycosylation.

Mohorko, E.Owen, R.L.Malojcic, G.Brozzo, M.S.Aebi, M.Glockshuber, R.

(2014) Structure 22: 590-601

  • DOI: https://doi.org/10.1016/j.str.2014.02.013
  • Primary Citation of Related Structures:  
    4M8G, 4M90, 4M91, 4M92

  • PubMed Abstract: 

    N-linked glycosylation of proteins in the endoplasmic reticulum (ER) is essential in eukaryotes and catalyzed by oligosaccharyl transferase (OST). Human OST is a hetero-oligomer of seven subunits. The subunit N33/Tusc3 is a tumor suppressor candidate, and defects in the subunit N33/Tusc3 are linked with nonsyndromic mental retardation. Here, we show that N33/Tusc3 possesses a membrane-anchored N-terminal thioredoxin domain located in the ER lumen that may form transient mixed disulfide complexes with OST substrates. X-ray structures of complexes between N33/Tusc3 and two different peptides as model substrates reveal a defined peptide-binding groove adjacent to the active site that can accommodate peptides in opposite orientations. Structural and biochemical data show that N33/Tusc3 prefers peptides bearing a hydrophobic residue two residues away from the cysteine forming the mixed disulfide with N33/Tusc3. Our results support a model in which N33/Tusc3 increases glycosylation efficiency for a subset of human glycoproteins by slowing glycoprotein folding.


  • Organizational Affiliation

    ETH Zürich, Department of Biology, Institute of Molecular Biology and Biophysics, Otto-Stern-Weg 5, 8093 Zurich, Switzerland.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Tumor suppressor candidate 3161Homo sapiensMutation(s): 1 
Gene Names: TUSC3N33
UniProt & NIH Common Fund Data Resources
Find proteins for Q13454 (Homo sapiens)
Explore Q13454 
Go to UniProtKB:  Q13454
PHAROS:  Q13454
GTEx:  ENSG00000104723 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ13454
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.186 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 38.66α = 90
b = 62.477β = 90
c = 64.598γ = 90
Software Package:
Software NamePurpose
PHASERphasing
PHENIXrefinement
REFMACrefinement
XDSdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-03-26
    Type: Initial release
  • Version 1.1: 2014-05-07
    Changes: Database references
  • Version 1.2: 2017-11-15
    Changes: Refinement description
  • Version 1.3: 2023-09-20
    Changes: Data collection, Database references, Derived calculations, Refinement description