3FEX

Crystal structure of the CBC-importin alpha complex.

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.549 Å
  • R-Value Free: 0.292 
  • R-Value Work: 0.217 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history. 

Literature

The molecular basis for the regulation of the cap-binding complex by the importins.

Dias, S.M., Wilson, K.F., Rojas, K.S., Ambrosio, A.L., Cerione, R.A.

(2009) Nat.Struct.Mol.Biol. 16: 930-937

  • DOI: 10.1038/nsmb.1649
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    • The binding of capped RNAs to the cap-binding complex (CBC) in the nucleus, and their dissociation from the CBC in the cytosol, represent essential steps in RNA processing. Here we show how the nucleocytoplasmic transport proteins importin-alpha and ...

    The binding of capped RNAs to the cap-binding complex (CBC) in the nucleus, and their dissociation from the CBC in the cytosol, represent essential steps in RNA processing. Here we show how the nucleocytoplasmic transport proteins importin-alpha and importin-beta have key roles in regulating these events. As a first step toward understanding the molecular basis for this regulation, we determined a 2.2-A resolution X-ray structure for a CBC-importin-alpha complex that provides a detailed picture for how importin-alpha binds to the CBP80 subunit of the CBC. Through a combination of biochemical studies, X-ray crystallographic information and small-angle scattering experiments, we then determined how importin-beta binds to the CBC through its CBP20 subunit. Together, these studies enable us to propose a model describing how importin-beta stimulates the dissociation of capped RNA from the CBC in the cytosol following its nuclear export.

    Organizational Affiliation: 

    Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Nuclear cap-binding protein subunit 1
A
790Homo sapiensMutation(s): 0 
Gene Names: NCBP1 (CBP80, NCBP)
Find proteins for Q09161 (Homo sapiens)
Go to Gene View: NCBP1
Go to UniProtKB:  Q09161
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Nuclear cap-binding protein subunit 2
B
156Homo sapiensMutation(s): 0 
Gene Names: NCBP2 (CBP20)
Find proteins for P52298 (Homo sapiens)
Go to Gene View: NCBP2
Go to UniProtKB:  P52298
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Importin subunit alpha-2
C
467Homo sapiensMutation(s): 0 
Gene Names: KPNA2 (RCH1, SRP1)
Find proteins for P52292 (Homo sapiens)
Go to Gene View: KPNA2
Go to UniProtKB:  P52292
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.549 Å
  • R-Value Free: 0.292 
  • R-Value Work: 0.217 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 83.508α = 90.00
b = 102.051β = 108.82
c = 107.878γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
HKL-2000data reduction
MOLREPphasing
HKL-2000data collection
PHENIXrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-08-11
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance