4M90

crystal structure of oxidized hN33/Tusc3


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.2 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: 10.1016/j.str.2014.02.013
  • Primary Citation of Related Structures:  

  • 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 ...

    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 Z├╝rich, Department of Biology, Institute of Molecular Biology and Biophysics, Otto-Stern-Weg 5, 8093 Zurich, Switzerland.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Tumor suppressor candidate 3
A
161Homo sapiensMutation(s): 1 
Gene Names: TUSC3 (N33)
Find proteins for Q13454 (Homo sapiens)
Go to Gene View: TUSC3
Go to UniProtKB:  Q13454
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.185 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 38.660α = 90.00
b = 62.477β = 90.00
c = 64.598γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
PHENIXrefinement
SCALAdata scaling
PHASERphasing
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-03-26
    Type: Initial release
  • Version 1.1: 2014-05-07
    Type: Database references
  • Version 1.2: 2017-11-15
    Type: Refinement description