Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 61.68 kDa 
• Atom Count: 4030 
• Residue Count: 509 
• Unique protein chains: 1

2B9R

Crystal Structure of Human Cyclin B1

• DOI: 10.2210/pdb2B9R/pdb

• Classification: CELL CYCLE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2005-10-12 Released: 2006-10-17 
• Deposition Author(s): Basavappa, R., Petri, E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.308 
• R-Value Work: 0.243 
• R-Value Observed: 0.249 

Literature

The Crystal Structure of Human Cyclin B.

Petri, E.T., Errico, A., Escobedo, L., Hunt, T., Basavappa, R.

(2007) Cell Cycle 6: 1342-1349

• PubMed: 17495533 
• DOI: 10.4161/cc.6.11.4297
• Primary Citation of Related Structures:  
  2B9R


• PubMed Abstract: 
  

Cyclin B is the key regulatory protein controlling mitosis in all eukaryotes, where it binds cyclin-dependent kinase, cdk1, forming a complex which initiates the mitotic program through phosphorylation of select proteins. Cyclin B regulates the activation, subcellular localization, and substrate specificity of cdk1, and destruction of cyclin B is necessary for mitotic exit. Overexpression of human cyclin B1 has been found in numerous cancers and has been associated with tumor aggressiveness. Here we report the crystal structure of human cyclin B1 to 2.9 A. Comparison of the structure with cyclin A and cyclin E reveals remarkably similar N-terminal cyclin box motifs but significant differences among the C-terminal cyclin box lobes. Divergence in sequence gives rise to unique interaction surfaces at the proposed cyclin B/cdk1 interface as well as the 'RxL' motif substrate binding site on cyclin B. Examination of the structure provides insight into the molecular basis for differential affinities of protein based cyclin/cdk inhibitors such as p27, substrate recognition, and cdk interaction.

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Organizational Affiliation: 

Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Human cyclin B1	A, B	269	Homo sapiens	Mutation(s): 5  Gene Names: CCNB1, CCNB
Find proteins for P14635 (Homo sapiens) Explore P14635  Go to UniProtKB:  P14635
NIH Common Fund Data Resources
PHAROS:  P14635 GTEx:  ENSG00000134057

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.308 
• R-Value Work: 0.243 
• R-Value Observed: 0.249 
• Space Group: P 6₂ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 117.169	α = 90
b = 117.169	β = 90
c = 197.685	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
DENZO	data reduction
d*TREK	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2005-10-12 
• Released Date: 2006-10-17 
Deposition Author(s): Basavappa, R., Petri, E.

Revision History 

• Version 1.0: 2006-10-17
  Type: Initial release
  
• Version 1.1: 2008-05-01
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Advisory, Version format compliance