3TJ3

Structure of importin a5 bound to the N-terminus of Nup50


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.702 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.215 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Nucleoporin Nup50 stabilizes closed conformation of armadillo repeat 10 in importin alpha 5.

Pumroy, R.A.Nardozzi, J.D.Hart, D.J.Root, M.J.Cingolani, G.

(2012) J.Biol.Chem. 287: 2022-2031

  • DOI: 10.1074/jbc.M111.315838

  • PubMed Abstract: 
  • The human genome encodes six isoforms of importin α that show greater than 60% sequence similarity and remarkable substrate specificity. The isoform importin α5 can bind phosphorylated cargos such as STAT1 and Epstein-Barr Virus Nuclear Antigen 1, as ...

    The human genome encodes six isoforms of importin α that show greater than 60% sequence similarity and remarkable substrate specificity. The isoform importin α5 can bind phosphorylated cargos such as STAT1 and Epstein-Barr Virus Nuclear Antigen 1, as well as the influenza virus polymerase subunit PB2. In this work, we have studied the interaction of the nucleoporin Nup50 with importin α5. We show that the first 47 residues of Nup50 bind to the C terminus of importin α5 like a "clip," stabilizing the closed conformation of ARM 10. In vitro, Nup50 binds with high affinity either to empty importin α5 or to a preassembled complex of importin α5 bound to the C-terminal domain of the import cargo PB2, resulting in a trimeric complex. By contrast, PB2 can only bind with high affinity to importin α5 in the absence of Nup50. This suggests that Nup50 primary function may not be to actively displace the import cargo from importin α5 but rather to prevent cargo rebinding in preparation for recycling. This is the first evidence for a nucleoporin modulating the import reaction by directly altering the three-dimensional structure of an import adaptor.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Importin subunit alpha-1
A, B
447Homo sapiensMutation(s): 0 
Gene Names: KPNA1 (RCH2)
Find proteins for P52294 (Homo sapiens)
Go to Gene View: KPNA1
Go to UniProtKB:  P52294
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Nuclear pore complex protein Nup50
C, D
114Homo sapiensMutation(s): 0 
Gene Names: NUP50 (NPAP60L)
Find proteins for Q9UKX7 (Homo sapiens)
Go to Gene View: NUP50
Go to UniProtKB:  Q9UKX7
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.702 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.215 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 81.683α = 90.00
b = 98.291β = 90.00
c = 135.352γ = 90.00
Software Package:
Software NamePurpose
ADSCdata collection
PHENIXrefinement
HKL-2000data reduction
PHASERphasing
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-11-30
    Type: Initial release
  • Version 1.1: 2015-02-11
    Type: Database references