Biological Assembly 1  

 3D View: Structure

Global Symmetry: Dihedral - D11  (3D View)
Global Stoichiometry: Hetero 704-mer - A176B176C176D176 Pseudo Symmetry: Dihedral - D11  (3D View)
Pseudo Stoichiometry: Homo 704-mer - A704 

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

Macromolecule Content

• Total Structure Weight: 108.51 kDa 
• Atom Count: 5700 
• Modelled Residue Count: 724 
• Deposited Residue Count: 980 
• Unique protein chains: 4

3C9K

Model of Histone Octamer Tubular Crystals

• DOI: 10.2210/pdb3C9K/pdb
• EMDataResource: EMD-1469

• Classification: DNA BINDING PROTEIN
• Organism(s): Gallus gallus
• Mutation(s): No 


• Deposited: 2008-02-16 Released: 2009-01-06 
• Deposition Author(s): Frouws, T.D.

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 20.0 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Literature

Histone octamer helical tubes suggest that an internucleosomal four-helix bundle stabilizes the chromatin fiber

Frouws, T.D., Patterton, H.G., Sewell, B.T.

(2009) Biophys J 96: 3363-3371

• PubMed: 19383479 
• DOI: 10.1016/j.bpj.2008.10.075
• Primary Citation of Related Structures:  
  3C9K


• PubMed Abstract: 
  

A major question in chromatin involves the exact organization of nucleosomes within the 30-nm chromatin fiber and its structural determinants of assembly. Here we investigate the structure of histone octamer helical tubes via the method of iterative helical real-space reconstruction. Accurate placement of the x-ray structure of the histone octamer within the reconstructed density yields a pseudoatomic model for the entire helix, and allows precise identification of molecular interactions between neighboring octamers. One such interaction that would not be obscured by DNA in the nucleosome consists of a twofold symmetric four-helix bundle formed between pairs of H2B-alpha3 and H2B-alphaC helices of neighboring octamers. We believe that this interface can act as an internucleosomal four-helix bundle within the context of the chromatin fiber. The potential relevance of this interface in the folding of the 30-nm chromatin fiber is discussed.

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Organizational Affiliation: 

Department of Biotechnology, University of the Western Cape, Cape Town, South Africa.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H2A-IV	A, E	128	Gallus gallus	Mutation(s): 0
Find proteins for P02263 (Gallus gallus) Explore P02263  Go to UniProtKB:  P02263

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H2B 7	B, F	125	Gallus gallus	Mutation(s): 0  Gene Names: H2B-VII
Find proteins for P0C1H5 (Gallus gallus) Explore P0C1H5  Go to UniProtKB:  P0C1H5

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H3.2	C, G	135	Gallus gallus	Mutation(s): 0  Gene Names: H3-I, H3-II, H3-III, H3-IV, H3-V, H3-VI, H3-VII, H3-VIII
Find proteins for P84229 (Gallus gallus) Explore P84229  Go to UniProtKB:  P84229

Entity ID: 4
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H4	D, H	102	Gallus gallus	Mutation(s): 0  Gene Names: H4-I, H4-II, H4-III, H4-IV, H4-V, H4-VI, H4-VII
Find proteins for P62801 (Gallus gallus) Explore P62801  Go to UniProtKB:  P62801

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 20.0 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2008-02-16 
• Released Date: 2009-01-06 
Deposition Author(s): Frouws, T.D.

Revision History  

• Version 1.0: 2009-01-06
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2012-09-05
  Changes: Database references
• Version 1.3: 2019-12-11
  Changes: Author supporting evidence, Data collection, Database references