4LCT

Crystal Structure and Versatile Functional Roles of the COP9 Signalosome Subunit 1


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.224 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Crystal structure and versatile functional roles of the COP9 signalosome subunit 1.

Lee, J.H.Yi, L.Li, J.Schweitzer, K.Borgmann, M.Naumann, M.Wu, H.

(2013) Proc.Natl.Acad.Sci.USA 110: 11845-11850

  • DOI: 10.1073/pnas.1302418110

  • PubMed Abstract: 
  • The constitutive photomorphogenesis 9 (COP9) signalosome (CSN) plays key roles in many biological processes, such as repression of photomorphogenesis in plants and protein subcellular localization, DNA-damage response, and NF-κB activation in mammals ...

    The constitutive photomorphogenesis 9 (COP9) signalosome (CSN) plays key roles in many biological processes, such as repression of photomorphogenesis in plants and protein subcellular localization, DNA-damage response, and NF-κB activation in mammals. It is an evolutionarily conserved eight-protein complex with subunits CSN1 to CSN8 named following the descending order of molecular weights. Here, we report the crystal structure of the largest CSN subunit, CSN1 from Arabidopsis thaliana (atCSN1), which belongs to the Proteasome, COP9 signalosome, Initiation factor 3 (PCI) domain containing CSN subunit family, at 2.7 Å resolution. In contrast to previous predictions and distinct from the PCI-containing 26S proteasome regulatory particle subunit Rpn6 structure, the atCSN1 structure reveals an overall globular fold, with four domains consisting of helical repeat-I, linker helix, helical repeat-II, and the C-terminal PCI domain. Our small-angle X-ray scattering envelope of the CSN1-CSN7 complex agrees with the EM structure of the CSN alone (apo-CSN) and suggests that the PCI end of each molecule may mediate the interaction. Fitting of the CSN1 structure into the CSN-Skp1-Cul1-Fbox (SCF) EM structure shows that the PCI domain of CSN1 situates at the hub of the CSN for interaction with several other subunits whereas the linker helix and helical repeat-II of CSN1 contacts SCF using a conserved surface patch. Furthermore, we show that, in human, the C-terminal tail of CSN1, a segment not included in our crystal structure, interacts with IκBα in the NF-κB pathway. Therefore, the CSN complex uses multiple mechanisms to hinder NF-κB activation, a principle likely to hold true for its regulation of many other targets and pathways.


    Organizational Affiliation

    Department of Biochemistry, Weill Cornell Medical College, New York, NY 10065, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
COP9 signalosome complex subunit 1
A, B, C, D
348Arabidopsis thalianaGene Names: CSN1 (COP11, FUS6)
Find proteins for P45432 (Arabidopsis thaliana)
Go to UniProtKB:  P45432
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B, C, D
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.224 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 202.210α = 90.00
b = 87.090β = 105.47
c = 133.600γ = 90.00
Software Package:
Software NamePurpose
ADSCdata collection
XDSdata scaling
XDSdata reduction
SHARPphasing
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-07-17
    Type: Initial release
  • Version 1.1: 2013-07-31
    Type: Database references