4LRW

Crystal Structure of K-Ras G12C (cysteine-light), GDP-bound

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.151 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.180 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history. 

Literature

K-Ras(G12C) inhibitors allosterically control GTP affinity and effector interactions.

Ostrem, J.M., Peters, U., Sos, M.L., Wells, J.A., Shokat, K.M.

(2013) Nature 503: 548-551

  • DOI: 10.1038/nature12796
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    • Somatic mutations in the small GTPase K-Ras are the most common activating lesions found in human cancer, and are generally associated with poor response to standard therapies. Efforts to target this oncogene directly have faced difficulties owing to ...

    Somatic mutations in the small GTPase K-Ras are the most common activating lesions found in human cancer, and are generally associated with poor response to standard therapies. Efforts to target this oncogene directly have faced difficulties owing to its picomolar affinity for GTP/GDP and the absence of known allosteric regulatory sites. Oncogenic mutations result in functional activation of Ras family proteins by impairing GTP hydrolysis. With diminished regulation by GTPase activity, the nucleotide state of Ras becomes more dependent on relative nucleotide affinity and concentration. This gives GTP an advantage over GDP and increases the proportion of active GTP-bound Ras. Here we report the development of small molecules that irreversibly bind to a common oncogenic mutant, K-Ras(G12C). These compounds rely on the mutant cysteine for binding and therefore do not affect the wild-type protein. Crystallographic studies reveal the formation of a new pocket that is not apparent in previous structures of Ras, beneath the effector binding switch-II region. Binding of these inhibitors to K-Ras(G12C) disrupts both switch-I and switch-II, subverting the native nucleotide preference to favour GDP over GTP and impairing binding to Raf. Our data provide structure-based validation of a new allosteric regulatory site on Ras that is targetable in a mutant-specific manner.

    Organizational Affiliation: 

    1] Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA [2].




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GTPase KRas
A, B
170Homo sapiensMutation(s): 3 
Gene Names: KRAS (KRAS2, RASK2)
Find proteins for P01116 (Homo sapiens)
Go to Gene View: KRAS
Go to UniProtKB:  P01116
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GDP
Query on GDP
Download SDF File 
Download CCD File 
A, B
GUANOSINE-5'-DIPHOSPHATE
C10 H15 N5 O11 P2
QGWNDRXFNXRZMB-UUOKFMHZSA-N
 Ligand Interaction
MG
Query on MG
Download SDF File 
Download CCD File 
A, B
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.151 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.180 
  • Space Group: P 3
Unit Cell:
Length (Å)Angle (°)
a = 82.862α = 90.00
b = 82.862β = 90.00
c = 38.397γ = 120.00
Software Package:
Software NamePurpose
BOSdata collection
SCALEPACKdata scaling
PDB_EXTRACTdata extraction
HKL-2000data reduction
PHASERphasing
HKL-2000data scaling
DENZOdata reduction
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots


View more in-depth experimental data

Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-11-27
    Type: Initial release
  • Version 1.1: 2013-12-18
    Type: Database references
  • Version 1.2: 2017-11-15
    Type: Refinement description