Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Hetero 4-mer - A2B2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 45.86 kDa 
• Atom Count: 2340 
• Modelled Residue Count: 286 
• Deposited Residue Count: 402 
• Unique protein chains: 3

4C31

Nup1:Sac3:Sus1 complex

• DOI: 10.2210/pdb4C31/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Saccharomyces cerevisiae
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2013-08-21 Released: 2014-04-16 
• Deposition Author(s): Stewart, M., Jani, D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.243 
• R-Value Work: 0.207 
• R-Value Observed: 0.209 

Literature

Structural Basis for Binding the Trex2 Complex to Nuclear Pores, Gal1 Localisation and Mrna Export.

Jani, D., Valkov, E., Stewart, M.

(2014) Nucleic Acids Res 42: 6686

• PubMed: 24705649 
• DOI: 10.1093/nar/gku252
• Primary Citation of Related Structures:  
  4C31, 4MBE


• PubMed Abstract: 
  

The conserved Sac3:Thp1:Sem1:Sus1:Cdc31 (TREX2) complex binds to nuclear pore complexes (NPCs) and, in addition to integrating mRNA nuclear export with preceding steps in the gene expression pathway, facilitates re-positioning of highly regulated actively transcribing genes (such as GAL1) to NPCs. Although TREX2 is thought to bind NPC protein Nup1, defining the precise role of this interaction has been frustrated by the complex pleiotropic phenotype exhibited by nup1Δ strains. To provide a structural framework for understanding the binding of TREX2 to NPCs and its function in the gene expression pathway, we have determined the structure of the Nup1:TREX2 interaction interface and used this information to engineer a Sac3 variant that impairs NPC binding while not compromising TREX2 assembly. This variant inhibited the NPC association of both de-repressed and activated GAL1 and also produced mRNA export and growth defects. These results indicate that the TREX2:Nup1 interaction facilitates the efficient nuclear export of bulk mRNA together with the re-positioning of GAL1 to NPCs that is required for transcriptional control that is mediated by removal of SUMO from repressors by NPC-bound Ulp1.

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Organizational Affiliation: 

MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, CB2 0QH, UK [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
NUCLEAR MRNA EXPORT PROTEIN SAC3	A, D	33	Saccharomyces cerevisiae	Mutation(s): 0
Find proteins for P46674 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore P46674  Go to UniProtKB:  P46674

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN SUS1	B, E	96	Saccharomyces cerevisiae	Mutation(s): 0
Find proteins for Q6WNK7 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore Q6WNK7  Go to UniProtKB:  Q6WNK7

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
NUCLEOPORIN NUP1	C, F, X, Y	36	Saccharomyces cerevisiae	Mutation(s): 0
Find proteins for P20676 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore P20676  Go to UniProtKB:  P20676

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.243 
• R-Value Work: 0.207 
• R-Value Observed: 0.209 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 95.55	α = 90
b = 95.55	β = 90
c = 105.66	γ = 120

Software Package:

Software Name	Purpose
PHENIX	refinement
MOSFLM	data reduction
SCALA	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-08-21 
• Released Date: 2014-04-16 
Deposition Author(s): Stewart, M., Jani, D.

Revision History  

• Version 1.0: 2014-04-16
  Type: Initial release
  
• Version 1.1: 2014-06-25
  Changes: Database references