Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A1B1C1 

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

Macromolecule Content

• Total Structure Weight: 36.64 kDa 
• Atom Count: 2506 
• Residue Count: 297 
• Unique protein chains: 3

3FWB

Sac3:Sus1:Cdc31 complex

• DOI: 10.2210/pdb3FWB/pdb

• Classification: cell cycle, transcription
• Organism(s): Saccharomyces cerevisiae
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2009-01-17 Released: 2009-04-14 
• Deposition Author(s): Stewart, M., Jani, D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.235 
• R-Value Work: 0.188 
• R-Value Observed: 0.191 

Literature

Sus1, Cdc31, and the Sac3 CID region form a conserved interaction platform that promotes nuclear pore association and mRNA export.

Jani, D., Lutz, S., Marshall, N.J., Fischer, T., Kohler, A., Ellisdon, A.M., Hurt, E., Stewart, M.

(2009) Mol Cell 33: 727-737

• PubMed: 19328066 
• DOI: 10.1016/j.molcel.2009.01.033
• Primary Citation of Related Structures:  
  3FWB, 3FWC


• PubMed Abstract: 
  

The yeast Sac3:Cdc31:Sus1:Thp1 (TREX-2) complex facilitates the repositioning and association of actively transcribing genes with nuclear pores (NPCs)-"gene gating"-that is central to integrating transcription, processing, and mRNA nuclear export. We present here the crystal structure of Sus1 and Cdc31 bound to a central region of Sac3 (the CID domain) that is crucial for its function. Sac3(CID) forms a long, gently undulating alpha helix around which one Cdc31 and two Sus1 chains are wrapped. Sus1 has an articulated helical hairpin fold that facilitates its wrapping around Sac3. In vivo studies using engineered mutations that selectively disrupted binding of individual chains to Sac3 indicated that Sus1 and Cdc31 function synergistically to promote NPC association of TREX-2 and mRNA nuclear export. These data indicate Sac3(CID) provides a scaffold within TREX-2 to integrate interactions between protein complexes to facilitate the coupling of transcription and mRNA export during gene expression.

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Organizational Affiliation: 

MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Cell division control protein 31	A	161	Saccharomyces cerevisiae	Mutation(s): 0  Gene Names: CDC31, DSK1, YOR257W
Find proteins for P06704 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore P06704  Go to UniProtKB:  P06704

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Nuclear mRNA export protein SAC3	B	55	Saccharomyces cerevisiae	Mutation(s): 0  Gene Names: LEP1, SAC3, YD8358.13, YDR159W
Find proteins for P46674 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore P46674  Go to UniProtKB:  P46674

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Protein SUS1	C	96	Saccharomyces cerevisiae	Mutation(s): 0  Gene Names: SUS1, YBR111W-A
Find proteins for Q6WNK7 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore Q6WNK7  Go to UniProtKB:  Q6WNK7

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.235 
• R-Value Work: 0.188 
• R-Value Observed: 0.191 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 53.535	α = 90
b = 60.062	β = 108.67
c = 77.3	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
PDB_EXTRACT	data extraction
ADSC	data collection
MOSFLM	data reduction
SCALA	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2009-01-17 
• Released Date: 2009-04-14 
Deposition Author(s): Stewart, M., Jani, D.

Revision History 

• Version 1.0: 2009-04-14
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Advisory, Version format compliance