2P8Q

Crystal Structure of human Importin beta bound to the Snurportin1 IBB-domain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.230 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Molecular Basis for the Recognition of Snurportin 1 by Importin {beta}.

Mitrousis, G.Olia, A.S.Walker-Kopp, N.Cingolani, G.

(2008) J Biol Chem 283: 7877-7884

  • DOI: https://doi.org/10.1074/jbc.M709093200
  • Primary Citation of Related Structures:  
    2P8Q, 2Q5D

  • PubMed Abstract: 

    The nuclear import of uridine-rich ribonucleoproteins is mediated by the transport adaptor snurportin 1 (SNP1). Similar to importin alpha, SNP1 uses an N-terminal importin beta binding (sIBB) domain to recruit the receptor importin beta and gain access to the nucleus. In this study, we demonstrate that the sIBB domain has a bipartite nature, which contains two distinct binding determinants for importin beta. The first determinant spans residues 25-65 and includes the previously identified importin alpha IBB (alphaIBB) region of homology. The second binding determinant encompasses residues 1-24 and resembles region 1011-1035 of the nucleoporin 153 (Nup153). The two binding determinants synergize within the sIBB domain to confer a low nanomolar binding affinity for importin beta (K(d) approximately 2 nm) in an interaction that, in vitro, is displaced by RanGTP. We propose that in vivo the synergy of Nup153 and nuclear RanGTP promotes translocation of uridine-rich ribonucleoproteins into the nucleus.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York 13210, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Importin beta-1 subunit876Homo sapiensMutation(s): 0 
Gene Names: KPNB1NTF97
UniProt & NIH Common Fund Data Resources
Find proteins for Q14974 (Homo sapiens)
Explore Q14974 
Go to UniProtKB:  Q14974
PHAROS:  Q14974
GTEx:  ENSG00000108424 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ14974
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Snurportin-140N/AMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for O95149 (Homo sapiens)
Explore O95149 
Go to UniProtKB:  O95149
GTEx:  ENSG00000169371 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO95149
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.230 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 64.752α = 90
b = 97.892β = 90.86
c = 84.286γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
AMoREphasing
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-01-22
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.2: 2023-08-30
    Changes: Data collection, Database references, Refinement description