6ASE

KRAS mutant-A59G in GDP-bound


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.554 Å
  • R-Value Free: 0.226 
  • R-Value Work: 0.196 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

KRAS Switch Mutants D33E and A59G Crystallize in the State 1 Conformation.

Lu, J.Bera, A.K.Gondi, S.Westover, K.D.

(2018) Biochemistry 57: 324-333

  • DOI: 10.1021/acs.biochem.7b00974
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • KRAS switch loop movements play a crucial role in regulating RAS signaling, and alteration of these sensitive dynamics is a principal mechanism through which disease-associated RAS mutations lead to aberrant RAS activation. Prior studies suggest that ...

    KRAS switch loop movements play a crucial role in regulating RAS signaling, and alteration of these sensitive dynamics is a principal mechanism through which disease-associated RAS mutations lead to aberrant RAS activation. Prior studies suggest that despite a high degree of sequence similarity, the switches in KRAS are more dynamic than those in HRAS. We determined X-ray crystal structures of the rare tumorigenic KRAS mutants KRAS D33E , in switch 1 (SW1), and KRAS A59G , in switch 2 (SW2), bound to GDP and found these adopt nearly identical, open SW1 conformations as well as altered SW2 conformations. KRAS A59G bound to a GTP analogue crystallizes in the same conformation. This open conformation is consistent with the inactive "state 1" previously observed for HRAS bound to GTP. For KRAS A59G , switch rearrangements may be regulated by increased flexibility in the 57 DXXGQ 61 motif at codon 59. However, loss of interactions between side chains at codons 33 and 35 in the SW1 33 DPT 35 motif drives changes for KRAS D33E . The 33 DPT 35 motif is conserved for multiple members of the RAS subfamily but is not found in RAB, RHO, ARF, or Gα families, suggesting that dynamics mediated by this motif may be important for determining the selectivity of RAS-effector interactions. Biochemically, the consequence of altered switch dynamics is the same, showing impaired interaction with the guanine exchange factor SOS and loss of GAP-dependent GTPase activity. However, interactions with the RBD of RAF are preserved. Overall, these observations add to a body of evidence suggesting that HRAS and KRAS show meaningful differences in functionality stemming from differential protein dynamics independent of the hypervariable region.


    Organizational Affiliation

    Departments of Biochemistry and Radiation Oncology, The University of Texas Southwestern Medical Center at Dallas , Dallas, Texas 75390, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GTPase KRas
A
170Homo sapiensMutation(s): 1 
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
GUANOSINE-5'-DIPHOSPHATE
C10 H15 N5 O11 P2
QGWNDRXFNXRZMB-UUOKFMHZSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.554 Å
  • R-Value Free: 0.226 
  • R-Value Work: 0.196 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 34.434α = 90.00
b = 47.428β = 90.00
c = 89.703γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
PDB_EXTRACTdata extraction
PHENIXrefinement
HKL-3000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2017-08-24 
  • Released Date: 2018-01-24 
  • Deposition Author(s): Westover, K., Lu, J.

Revision History 

  • Version 1.0: 2018-01-24
    Type: Initial release
  • Version 1.1: 2018-02-07
    Type: Database references