PMID- 10359839
OWN - NLM
STAT- MEDLINE
DCOM- 19990708
LR  - 20190501
IS  - 0027-8424 (Print)
IS  - 1091-6490 (Electronic)
IS  - 0027-8424 (Linking)
VI  - 96
IP  - 12
DP  - 1999 Jun 8
TI  - Guanosine triphosphatase stimulation of oncogenic Ras mutants.
PG  - 7065-70
AB  - Interest in the guanosine triphosphatase (GTPase) reaction of Ras as a molecular 
      drug target stems from the observation that, in a large number of human tumors, 
      Ras is characteristically mutated at codons 12 or 61, more rarely 13. Impaired 
      GTPase activity, even in the presence of GTPase activating proteins, has been 
      found to be the biochemical reason behind the oncogenicity of most Gly12/Gln61 
      mutations, thus preventing Ras from being switched off. Therefore, these 
      oncogenic Ras mutants remain constitutively activated and contribute to the 
      neoplastic phenotype of tumor cells. Here, we show that the guanosine 
      5'-triphosphate (GTP) analogue diaminobenzophenone-phosphoroamidate-GTP 
      (DABP-GTP) is hydrolyzed by wild-type Ras but more efficiently by frequently 
      occurring oncogenic Ras mutants, to yield guanosine 5'-diphosphate-bound inactive 
      Ras and DABP-Pi. The reaction is independent of the presence of Gln61 and is most 
      dramatically enhanced with Gly12 mutants. Thus, the defective GTPase reaction of 
      the oncogenic Ras mutants can be rescued by using DABP-GTP instead of GTP, 
      arguing that the GTPase switch of Ras is not irreversibly damaged. An exocyclic 
      aromatic amino group of DABP-GTP is critical for the reaction and bypasses the 
      putative rate-limiting step of the intrinsic Ras GTPase reaction. The crystal 
      structures of Ras-bound DABP-beta,gamma-imido-GTP show a disordered switch I and 
      identify the Gly12/Gly13 region as the hydrophobic patch to accommodate the 
      DABP-moiety. The biochemical and structural studies help to define the 
      requirements for the design of anti-Ras drugs aimed at the blocked GTPase 
      reaction.
FAU - Ahmadian, M R
AU  - Ahmadian MR
AD  - Abteilung Strukturelle Biologie, Max-Planck-Institut fur molekulare Physiologie, 
      Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
FAU - Zor, T
AU  - Zor T
FAU - Vogt, D
AU  - Vogt D
FAU - Kabsch, W
AU  - Kabsch W
FAU - Selinger, Z
AU  - Selinger Z
FAU - Wittinghofer, A
AU  - Wittinghofer A
FAU - Scheffzek, K
AU  - Scheffzek K
LA  - eng
SI  - PDB/1CLU
SI  - PDB/1RVD
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (3,4-diaminobenzophenone-phosphonoamidate-GTP)
RN  - 0 (Benzophenones)
RN  - 86-01-1 (Guanosine Triphosphate)
RN  - EC 3.6.1.- (GTP Phosphohydrolases)
RN  - EC 3.6.5.2 (ras Proteins)
SB  - IM
MH  - Benzophenones/*analysis/chemistry/metabolism
MH  - Crystallography, X-Ray
MH  - Escherichia coli
MH  - GTP Phosphohydrolases/genetics/metabolism
MH  - *Genes, ras
MH  - Guanosine Triphosphate/*analogs & 
      derivatives/analysis/chemistry/genetics/metabolism
MH  - Humans
MH  - Hydrolysis
MH  - Molecular Sequence Data
MH  - *Mutation
MH  - Protein Binding
MH  - ras Proteins/*genetics/*metabolism
PMC - PMC22057
EDAT- 1999/06/09 00:00
MHDA- 1999/06/09 00:01
PMCR- 1999/12/08
CRDT- 1999/06/09 00:00
PHST- 1999/06/09 00:00 [pubmed]
PHST- 1999/06/09 00:01 [medline]
PHST- 1999/06/09 00:00 [entrez]
PHST- 1999/12/08 00:00 [pmc-release]
AID - 0406 [pii]
AID - 10.1073/pnas.96.12.7065 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 1999 Jun 8;96(12):7065-70. doi: 
      10.1073/pnas.96.12.7065.