Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors and generated by PQS (software)

Macromolecule Content

• Total Structure Weight: 107.69 kDa 
• Atom Count: 6961 
• Residue Count: 815 
• Unique protein chains: 2

1H2V

Structure of the human nuclear cap-binding-complex (CBC)

• DOI: 10.2210/pdb1H2V/pdb

• Classification: NUCLEAR PROTEIN
• Organism(s): Homo sapiens
• Expression System: Trichoplusia ni, Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 2002-08-16 Released: 2002-10-17 
• Deposition Author(s): Mazza, C., Segref, A., Mattaj, I.W., Cusack, S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.247 
• R-Value Work: 0.212 
• R-Value Observed: 0.212 

Literature

Large-Scale Induced Fit Recognition of an M(7)Gpppg CAP Analogue by the Human Nuclear CAP-Binding Complex

Mazza, C., Segref, A., Mattaj, I.W., Cusack, S.

(2002) EMBO J 21: 5548

• PubMed: 12374755 
• DOI: 10.1093/emboj/cdf538
• Primary Citation of Related Structures:  
  1H2V, 1H2U, 1H2T


• PubMed Abstract: 
  

The heterodimeric nuclear cap-binding complex (CBC) binds to the 5' cap structure of RNAs in the nucleus and plays a central role in their diverse maturation steps. We describe the crystal structure at 2.1 A resolution of human CBC bound to an m(7)GpppG cap analogue. Comparison with the structure of uncomplexed CBC shows that cap binding induces co-operative folding around the dinucleotide of some 50 residues from the N- and C-terminal extensions to the central RNP domain of the small subunit CBP20. The cap-bound conformation of CBP20 is stabilized by an intricate network of interactions both to the ligand and within the subunit, as well as new interactions of the CBP20 N-terminal tail with the large subunit CBP80. Although the structure is very different from that of other known cap-binding proteins, such as the cytoplasmic cap-binding protein eIF4E, specificity for the methylated guanosine again is achieved by sandwiching the base between two aromatic residues, in this case two conserved tyrosines. Implications for the transfer of capped mRNAs to eIF4E, required for translation initiation, are discussed.

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Related Citations: 

• Co-Crystallization of the Human Nuclear CAP-Binding Complex with a M7Gpppg CAP Analogue Using Protein Engineering
  Mazza, C., Segref, A., Mattaj, I., Cusack, S.
  (2002) Acta Crystallogr D Biol Crystallogr 58: 2194

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Organizational Affiliation: 

European Molecular Biology Laboratory, Grenoble Outstation, c/o ILL, BP 181, F-38042 Grenoble cedex 9, France.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
80 KDA NUCLEAR CAP BINDING PROTEIN	C	771	Homo sapiens	Mutation(s): 1  Gene Names: NCBP1, CBP80, NCBP
Find proteins for Q09161 (Homo sapiens) Explore Q09161  Go to UniProtKB:  Q09161
NIH Common Fund Data Resources
PHAROS  Q09161 GTEx  ENSG00000136937

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
20 KDA NUCLEAR CAP BINDING PROTEIN	Z	156	Homo sapiens	Mutation(s): 0  Gene Names: NCBP2, CBP20, PIG55
Find proteins for P52298 (Homo sapiens) Explore P52298  Go to UniProtKB:  P52298
NIH Common Fund Data Resources
PHAROS  P52298 GTEx  ENSG00000114503

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.247 
• R-Value Work: 0.212 
• R-Value Observed: 0.212 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 264.136	α = 90
b = 59.605	β = 99.52
c = 75.43	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
XDS	data reduction
XSCALE	data scaling
MOLREP	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2002-08-16 
• Released Date: 2002-10-17 
Deposition Author(s): Mazza, C., Segref, A., Mattaj, I.W., Cusack, S.

Revision History 

• Version 1.0: 2002-10-17
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2019-04-03
  Changes: Data collection, Other, Source and taxonomy