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 

wwPDB Validation 3D Report Full Report


This is version 1.1 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: 10.1074/jbc.M709093200
  • Primary Citation of Related Structures:  

  • 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 acce ...

    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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Importin beta-1 subunit
A
876Homo sapiensMutation(s): 0 
Gene Names: KPNB1 (NTF97)
Find proteins for Q14974 (Homo sapiens)
Go to Gene View: KPNB1
Go to UniProtKB:  Q14974
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Snurportin-1
B
40Homo sapiensMutation(s): 0 
Gene Names: SNUPN (RNUT1, SPN1)
Find proteins for O95149 (Homo sapiens)
Go to Gene View: SNUPN
Go to UniProtKB:  O95149
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.227 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 64.752α = 90.00
b = 97.892β = 90.86
c = 84.286γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
CNSrefinement
SCALEPACKdata scaling
AMoREphasing
HKL-2000data collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-01-22
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Derived calculations, Version format compliance