1IHB

CRYSTAL STRUCTURE OF P18-INK4C(INK6)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.209 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure of the CDK4/6 inhibitory protein p18INK4c provides insights into ankyrin-like repeat structure/function and tumor-derived p16INK4 mutations.

Venkataramani, R.Swaminathan, K.Marmorstein, R.

(1998) Nat Struct Biol 5: 74-81

  • DOI: 10.1038/nsb0198-74
  • Primary Citation of Related Structures:  
    1IHB

  • PubMed Abstract: 
  • p18INK4c is a member of a family of INK4 proteins that function to arrest the G1 to S cell cycle transition by inhibiting the activity of the cyclin-dependent kinases 4 and 6. The X-ray crystal structure of the human p18INK4c protein to a resolution ...

    p18INK4c is a member of a family of INK4 proteins that function to arrest the G1 to S cell cycle transition by inhibiting the activity of the cyclin-dependent kinases 4 and 6. The X-ray crystal structure of the human p18INK4c protein to a resolution of 1.95 A reveals an elongated molecule comprised of five contiguous 32- or 33-residue ankyrin-like repeat units. Each ankyrin-like repeat contains a beta-strand helix-turn-helix extended strand beta-strand motif that associates with neighboring motifs through beta-sheet, and helical bundle interactions. Conserved ankyrin-like repeat residues function to facilitate the ankyrin repeat fold and the tertiary interactions between neighboring repeat units. A large percentage of residues that are conserved among INK4 proteins and that map to positions of tumor-derived p16INK4 mutations play important roles in protein stability. A subset of these residues suggest an INK4 binding surface for the cyclin-dependent kinases 4 and 6. This surface is centered around a region that shows structural features uncharacteristic of ankyrin-like repeat units.


    Organizational Affiliation

    Wistar Institute, Philadelphia, Pennsylvania, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CYCLIN-DEPENDENT KINASE 6 INHIBITORAB162Homo sapiensMutation(s): 0 
Gene Names: P18-INK4C(INK6)CDKN2CCDKN6
Find proteins for P42773 (Homo sapiens)
Explore P42773 
Go to UniProtKB:  P42773
NIH Common Fund Data Resources
PHAROS  P42773
Protein Feature View
Expand
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.209 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 55.51α = 90
b = 151.7β = 90
c = 40.46γ = 90
Software Package:
Software NamePurpose
PHASESphasing
X-PLORrefinement
DENZOdata reduction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1998-12-02
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance