Primary Citation of Related Structures:   1NF1
PubMed Abstract: 
Neurofibromin is the product of the NF1 gene, whose alteration is responsible for the pathogenesis of neurofibromatosis type 1 (NF1), one of the most frequent genetic disorders in man. It acts as a GTPase activating protein (GAP) on Ras; based on homology to p120GAP, a segment spanning 250-400 aa and termed GAP-related domain (NF1GRD; 25-40 kDa) has been shown to be responsible for GAP activity and represents the only functionally defined segment of neurofibromin ...
Neurofibromin is the product of the NF1 gene, whose alteration is responsible for the pathogenesis of neurofibromatosis type 1 (NF1), one of the most frequent genetic disorders in man. It acts as a GTPase activating protein (GAP) on Ras; based on homology to p120GAP, a segment spanning 250-400 aa and termed GAP-related domain (NF1GRD; 25-40 kDa) has been shown to be responsible for GAP activity and represents the only functionally defined segment of neurofibromin. Missense mutations found in NF1 patients map to NF1GRD, underscoring its importance for pathogenesis. X-ray crystallographic analysis of a proteolytically treated catalytic fragment of NF1GRD comprising residues 1198-1530 (NF1-333) of human neurofibromin reveals NF1GRD as a helical protein that resembles the corresponding fragment derived from p120GAP (GAP-334). A central domain (NF1c) containing all residues conserved among RasGAPs is coupled to an extra domain (NF1ex), which despite very limited sequence homology is surprisingly similar to the corresponding part of GAP-334. Numerous point mutations found in NF1 patients or derived from genetic screening protocols can be analysed on the basis of the three-dimensional structural model, which also allows identification of the site where structural changes in a differentially spliced isoform are to be expected. Based on the structure of the complex between Ras and GAP-334 described earlier, a model of the NF1GRD-Ras complex is proposed which is used to discuss the strikingly different properties of the Ras-p120GAP and Ras-neurofibromin interactions.
Related Citations: 
The Ras-Rasgap Complex: Structural Basis for Gtpase Activation and its Loss in Oncogenic Ras Mutants Scheffzek, K., Ahmadian, M.R., Kabsch, W., Wiesmueller, L., Lautwein, A., Schmitz, F., Wittinghofer, A. (1997) Science 277: 333
Confirmation of the Arginine-Finger Hypothesis for the Gap-Stimulated GTP- Hydrolysis Reaction of Ras Ahmadian, M.R., Stege, P., Scheffzek, K., Wittinghofer, A. (1997) Nat Struct Biol 4: 686
Structural Differences in the Minimal Catalytic Domains of the Gtpasse- Activating Proteins P120Gap and Neurofibromin Ahmadian, M.R., Wiesmueller, L., Lautwein, A., Bischoff, F.R., Wittinghofer, A. (1996) J Biol Chem 271: 16409
3-Dimensional 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
Formation of a Transition-State Analog of the Ras Gtpase Reaction by Ras:Gdp, Tetrafluoroaluminate and Gtpase-Activating Proteins Mittal, R., Ahmadian, M.R., Goody, R.S., Wittinghofer, A. (1996) Science 273: 115
The Neurofibromatosis Type I Gene and its Protein Product Gutmann, D.H., Collins, F.S. (1993) Neuron 10: 335
The NF1 Locus Encodes a Protein Functionally Related to Mammalian Gap and Yeast Ira Proteins Ballester, R., Marchuk, D., Boguski, M., Saulino, A., Letcher, R., Wigler, M., Collins, F. (1990) Cell 63: 851
The Gap-Related Domain of the Neurofibromatosis Type I Gene Product Interacts with Ras P21 Martin, G.A., Viskochil, D., Bollag, G., Mccabe, P.C., Crosier, W.J., Hausbruck, H., Conroy, L., Clark, R., O'Connell, P., Cawthon, R.M., Innis, M.A., Mccormick, F. (1990) Cell 63: 843
The Catalytic Domain of the Neurofibromatosis Type I Gene Product Stimulates Ras Gtpase and Complements Ira Mutants of S. Cerevisiae Xu, G., Lin, B., Tanaka, K., Dunn, D., Wod, D., Gesteland, R., White, R., Weiss, R., Tamanoi, F. (1990) Cell 63: 835
Refined Crystal Structure of the Triphosphate Conformation of H-Ras P21 at 1.35 A Resolution: Implications for the Mechanism of GTP Hydrolysis Pai, E.F., Krengel, U., Petsko, G.A., Goody, R.S., Kabsch, W., Wittinghofer, A. (1990) EMBO J 9: 2351
Organizational Affiliation: 
Max-Planck-Institut für molekulare Physiologie, Dortmund, Germany. Klas.Scheffzek@mpi-dortmund.mpg.de