1GCJ

N-TERMINAL FRAGMENT OF IMPORTIN-BETA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.215 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The adoption of a twisted structure of importin-beta is essential for the protein-protein interaction required for nuclear transport.

Lee, S.J.Imamoto, N.Sakai, H.Nakagawa, A.Kose, S.Koike, M.Yamamoto, M.Kumasaka, T.Yoneda, Y.Tsukihara, T.

(2000) J.Mol.Biol. 302: 251-264

  • DOI: 10.1006/jmbi.2000.4055

  • PubMed Abstract: 
  • Importin-beta is a nuclear transport factor which mediates the nuclear import of various nuclear proteins. The N-terminal 1-449 residue fragment of mouse importin-beta (impbeta449) possesses the ability to bidirectionally translocate through the nucl ...

    Importin-beta is a nuclear transport factor which mediates the nuclear import of various nuclear proteins. The N-terminal 1-449 residue fragment of mouse importin-beta (impbeta449) possesses the ability to bidirectionally translocate through the nuclear pore complex (NPC), and to bind RanGTP. The structure of the uncomplexed form of impbeta449 has been solved at a 2.6 A resolution by X-ray crystallography. It consists of ten copies of the tandemly arrayed HEAT repeat and exhibits conformational flexibility which is involved in protein-protein interaction for nuclear transport. The overall conformation of the HEAT repeats shows that a twisted motion produces a significantly varied superhelical architecture from the previously reported structure of RanGTP-bound importin-beta. These conformational changes appear to be the sum of small conformational changes throughout the polypeptide. Such a flexibility, which resides in the stacked HEAT repeats, is essential for interaction with RanGTP or with NPCs. Furthermore, it was found that impbeta449 has a structural similarity with another nuclear migrating protein, namely beta-catenin, which is composed of another type of helix-repeated structure of ARM repeat. Interestingly, the essential regions for NPC translocation for both importin-beta and beta-catenin are spatially well overlapped with one another. This strongly indicates the importance of helix stacking of the HEAT or ARM repeats for NPC-passage.


    Organizational Affiliation

    Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Osaka, Suita, 565-0871, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
IMPORTIN BETA
A, B
460Mus musculusGene Names: Kpnb1 (Impnb)
Find proteins for P70168 (Mus musculus)
Go to UniProtKB:  P70168
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.215 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 81.830α = 90.00
b = 103.780β = 90.00
c = 126.940γ = 90.00
Software Package:
Software NamePurpose
MLPHAREphasing
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-10-18
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance