Crystal structure of the GTPase-activating domain of human p120GAP and implications for the interaction with Ras.Scheffzek, K., Lautwein, A., Kabsch, W., Ahmadian, M.R., Wittinghofer, A.
(1996) Nature 384: 591-596
- PubMed: 8955277
- DOI: 10.1038/384591a0
- Primary Citation of Related Structures:
- PubMed Abstract:
- Crystallization and Preliminary X-Ray Crystallographic Study of the Ras-Gtpase-Activating Domain of Human P120Gap
Scheffzek, K., Lautwein, A., Scherer, A., Franken, S., Wittinghofer, A.
(1997) Proteins 27: 315
- Molecular Cloning of Two Types of Gap Complementary DNA from Human Placenta
Trahey, M., Wong, G., Halenbeck, R., Rubinfeld, B., Martin, G.A., Ladner, M., Long, C.M., Crosier, W.J., Watt, K., Koths, K., Mccormick, F.
(1988) Science 242: 1697
- A Cytoplasmic Protein Stimulates Normal N-Ras P21 Gtpase, But Does not Affect Oncogenic Mutants
Trahey, M., Mccormick, F.
(1987) Science 238: 542
Ras-related GTP-binding proteins function as molecular switches which cycle between GTP-bound 'on'- and GDP-bound 'off'-states. GTP hydrolysis is the common timing mechanism that mediates the return from the 'on' to the 'off'-state. It is usually slow bu ...
Ras-related GTP-binding proteins function as molecular switches which cycle between GTP-bound 'on'- and GDP-bound 'off'-states. GTP hydrolysis is the common timing mechanism that mediates the return from the 'on' to the 'off'-state. It is usually slow but can be accelerated by orders of magnitude upon interaction with GTPase-activating proteins (GAPs). In the case of Ras, a major regulator of cellular growth, point mutations are found in approximately 30% of human tumours which render the protein unable to hydrolyse GTP, even in the presence of Ras-GAPs. The first structure determination of a GTPase-activating protein reveals the catalytically active fragment of the Ras-specific p120GAP (ref. 2), GAP-334, as an elongated, exclusively helical protein which appears to represent a novel protein fold. The molecule consists of two domains, one of which contains all the residues conserved among different GAPs for Ras. From the location of conserved residues around a shallow groove in the central domain we can identify the site of interaction with Ras x GTP. This leads to a model for the interaction between Ras and GAP that satisfies numerous biochemical and genetic data on this important regulatory process.
Max-Planck-Institut für molekulare Physiologie, Dortmund, Germany.