Key Points
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Human Rho GTPases (of which there are 22 members) comprise a main branch of the Ras superfamily of small GTPases and GDP/GTP-regulated molecular switches. Rho GTPases are activated by the direct engagement of guanine nucleotide-exchange factors (GEFs), which catalyse the ejection of GTPase-bound GDP and the loading of GTP. In humans, the ∼70 Dbl-family proteins comprise the largest group of Rho GEFs.
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Dbl-family proteins are characterized by a catalytic Dbl homology (DH) domain that is immediately adjacent to a regulatory C-terminal pleckstrin homology (PH) domain. DH domains engage the flexible switch regions of GTPases, which leads to their remodelling and the exchange of nucleotides. PH domains assist in this process by less well understood, and more varied, mechanisms.
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In most scenarios, PH domains are thought to bind weakly to phosphoinositides to facilitate GDP/GTP exchange. The binding of phosphoinositides has been proposed to facilitate this exchange by causing allosteric changes within the DH–PH array. However, it is more likely that phosphoinositide binding functions to guide the precise subcellular localization of Dbl proteins, and to orientate DH–PH arrays at lipid bilayers to promote the productive engagement of membrane-bound GTPases.
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Dbl proteins function to integrate diverse extracellular stimuli — for example, signals from heterotrimeric G-protein-coupled- or tyrosine-kinase-associated receptors that control the spatio-temporal activation of Rho GTPases. Regulatory mechanisms include the intramolecular autoinhibition of Dbl proteins, which can be relieved by various inputs — most notably, phosphorylation. It is likely that the flux of phosphoinositide levels regulates the exchange activity of Dbl proteins.
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In addition to Dbl proteins, Dock-family human proteins (11 members), as well as bacterial proteins, expand the diversity of proteins that function as GEFs and activators of Rho GTPases.
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The contribution of aberrant Rho-GTPase function to human disease is supported by the association of mutated Dbl-family proteins with cancer, developmental and neurological disorders. Furthermore, viral and bacterial pathogens manipulate Rho GEFs to facilitate their invasion and pathogenicity of human cells.
Abstract
Guanine nucleotide-exchange factors (GEFs) are directly responsible for the activation of Rho-family GTPases in response to diverse extracellular stimuli, and ultimately regulate numerous cellular responses such as proliferation, differentiation and movement. With 69 distinct homologues, Dbl-related GEFs represent the largest family of direct activators of Rho GTPases in humans, and they activate Rho GTPases within particular spatio-temporal contexts. The failure to do so can have significant consequences and is reflected in the aberrant function of Dbl-family GEFs in some human diseases.
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References
Van Aelst, L. & D'Souza-Schorey, C. Rho GTPases and signaling networks. Genes Dev. 11, 2295–2322 (1997).
Bishop, A. L. & Hall, A. Rho GTPases and their effector proteins. Biochem. J. 348, 241–255 (2000).
Kjoller, L. & Hall, A. Signaling to Rho GTPases. Exp. Cell Res. 253, 166–179 (1999).
Sah, V. P., Seasholtz, T. M., Sagi, S. A. & Brown, J. H. The role of Rho in G protein-coupled receptor signal transduction. Annu. Rev. Pharmacol. Toxicol. 40, 459–489 (2000).
Evers, E. E. et al. Rho family proteins in cell adhesion and cell migration. Eur. J. Cancer 36, 1269–1274 (2000).
Chimini, G. & Chavrier, P. Function of Rho family proteins in actin dynamics during phagocytosis and engulfment. Nature Cell Biol. 2, E191–E196 (2000).
Etienne-Manneville, S. & Hall, A. Rho GTPases in cell biology. Nature 420, 629–635 (2002).
Raftopoulou, M. & Hall, A. Cell migration: Rho GTPases lead the way. Dev. Biol. 265, 23–32 (2004).
Sahai, E. & Marshall, C. J. RHO-GTPases and cancer. Nature Rev. Cancer 2, 133–142 (2002).
Eva, A., Vecchio, G., Rao, C. D., Tronick, S. R. & Aaronson, S. A. The predicted DBL oncogene product defines a distinct class of transforming proteins. Proc. Natl Acad. Sci. USA 85, 2061–2065 (1988).
Hart, M. J., Eva, A., Evans, T., Aaronson, S. A. & Cerione, R. A. Catalysis of guanine nucleotide exchange on the CDC42Hs protein by the dbl oncogene product. Nature 354, 311–314 (1991). Seminal paper showing the first direct activation of a Rho GTPase by a Dbl protein.
Schmidt, A. & Hall, A. Guanine nucleotide exchange factors for Rho GTPases: turning on the switch. Genes Dev. 16, 1587–1609 (2002).
Worthylake, D. K., Rossman, K. L. & Sondek, J. Crystal structure of Rac1 in complex with the guanine nucleotide exchange region of Tiam1. Nature 408, 682–688 (2000). Original structure of a DH–PH-domain fragment bound to a nucleotide-depleted GTPase and used to define the mechanism of nucleotide exchange.
Liu, X. et al. NMR structure and mutagenesis of the N-terminal Dbl homology domain of the nucleotide exchange factor Trio. Cell 95, 269–277 (1998).
Soisson, S. M., Nimnual, A. S., Uy, M., Bar-Sagi, D. & Kuriyan, J. Crystal structure of the Dbl and pleckstrin homology domains from the human Son of sevenless protein. Cell 95, 259–268 (1998). The first structure showing the interdomain arrangement of a DH domain and its associated PH domain.
Aghazadeh, B. et al. Structure and mutagenesis of the Dbl homology domain. Nature Struct. Biol. 5, 1098–1107 (1998).
Aghazadeh, B., Lowry, W. E., Huang, X. Y. & Rosen, M. K. Structural basis for relief of autoinhibition of the Dbl homology domain of proto-oncogene Vav by tyrosine phosphorylation. Cell 102, 625–633 (2000). This structure of Vav highlights the autoinhibition of the DH domain by steric exclusion, which is relieved on phosphorylation.
Rossman, K. L. et al. A crystallographic view of interactions between Dbs and Cdc42, PH domain-assisted guanine nucleotide exchange. EMBO J. 21, 1315–1326 (2002).
Snyder, J. T. et al. Structural basis for the selective activation of Rho GTPases by Dbl exchange factors. Nature Struct. Biol. 9, 468–475 (2002).
Worthylake, D. K., Rossman, K. L. & Sondek, J. Crystal structure of the DH/PH fragment of Dbs without bound GTPase. Structure 12, 1078–1086 (2004).
Skowronek, K. R., Guo, F., Zheng, Y. & Nassar, N. The C-terminal basic tail of RhoG assists the guanine nucleotide exchange factor Trio in binding to phospholipids. J. Biol. Chem. 279, 37895–37907 (2004).
Kristelly, R., Gao, G. & Tesmer, J. J. Structural determinants of RhoA binding and nucleotide exchange in leukemia-associated RhoGEF. J. Biol. Chem. 279, 47352–47362 (2004).
Sondermann, H., Soisson, S. M., Boykevisch, S., Yang, S. S., Bar-Sagi, D. & Kuriyan, J. Structural analysis of autoinhibition in the Ras activator Son of sevenless. Cell 119, 393–405 (2004).
Boriack-Sjodin, P. A., Margarit, S. M., Bar-Sagi, D. & Kuriyan, J. The structural basis of the activation of Ras by Sos. Nature 394, 337–343 (1998).
Goldberg, J. Structural basis for activation of ARF GTPase, mechanisms of guanine nucleotide exchange and GTP-myristoyl switching. Cell 95, 237–248 (1998).
Renault, L., Kuhlmann, J., Henkel, A. & Wittinghofer, A. Structural basis for guanine nucleotide exchange on Ran by the regulator of chromosome condensation (RCC1). Cell 105, 245–255 (2001).
Shimizu, T. et al. An open conformation of switch I revealed by the crystal structure of a Mg2+-free form of RHOA complexed with GDP. Implications for the GDP/GTP exchange mechanism. J. Biol. Chem. 275, 18311–18317 (2000).
Buchwald, G. et al. Structural basis for the reversible activation of a Rho protein by the bacterial toxin SopE. EMBO J. 21, 3286–3295 (2002).
Rossman, K. L. et al. Functional analysis of cdc42 residues required for guanine nucleotide exchange. J. Biol. Chem. 277, 50893–50898 (2002).
Karnoub, A. E. et al. Molecular basis for Rac1 recognition by guanine nucleotide exchange factors. Nature Struct. Biol. 8, 1037–1041 (2001).
Cheng, L. et al. RhoGEF specificity mutants implicate RhoA as a target for Dbs transforming activity. Mol. Cell. Biol. 22, 6895–6905 (2002).
Rossman, K. L. & Campbell, S. L. Bacterial expressed DH and DH/PH domains. Methods Enzymol. 325, 25–38 (2000).
Rossman, K. L. et al. Multifunctional roles for the PH domain of Dbs in regulating Rho GTPase activation. J. Biol. Chem. 278, 18393–18400 (2003).
Ron, D. et al. A region of proto-dbl essential for its transforming activity shows sequence similarity to a yeast cell cycle gene, CDC24, and the human breakpoint cluster gene, bcr. New Biol. 3, 372–379 (1991).
Whitehead, I. P., Kirk, H., Tognon, C., Trigo-Gonzalez, G. & Kay, R. Expression cloning of lfc, a novel oncogene with structural similarities to guanine nucleotide exchange factors and to the regulatory region of protein kinase C. J. Biol. Chem. 271, 18388–18395 (1995).
Ferguson, K. M., Lemmon, M. A., Schlessinger, J. & Sigler, P. B. Structure of the high affinity complex of inositol trisphosphate with a phospholipase C pleckstrin homology domain. Cell 83, 1037–1046 (1995).
Snyder, J. T. et al. Quantitative analysis of the effect of phosphoinositide interactions on the function of Dbl family proteins. J. Biol. Chem. 276, 45868–45875 (2001).
Chen, R. H., Corbalan-Garcia, S. & Bar-Sagi, D. The role of the PH domain in the signal-dependent membrane targeting of Sos. EMBO J. 16, 1351–1359 (1997).
Baumeister, M. A. et al. Loss of phosphatidylinositol 3-phosphate binding by the C-terminal Tiam-1 pleckstrin homology domain prevents in vivo Rac1 activation without affecting membrane targeting. J. Biol. Chem. 278, 11457–11464 (2003).
Stam, J. C. et al. Targeting of Tiam1 to the plasma membrane requires the cooperative function of the N-terminal pleckstrin homology domain and an adjacent protein interaction domain. J. Biol. Chem. 272, 28447–28454 (1997).
Das, B. et al. Control of intramolecular interactions between the pleckstrin homology and Dbl homology domains of Vav and Sos1 regulates Rac binding. J. Biol. Chem. 275, 15074–15081 (2000).
Crompton, A. M. et al. Regulation of Tiam1 nucleotide exchange activity by pleckstrin domain binding ligands. J. Biol. Chem. 275, 25751–25759 (2000).
Russo, C. et al. Modulation of oncogenic DBL activity by phosphoinositol phosphate binding to pleckstrin homology domain. J. Biol. Chem. 276, 19524–19531 (2001).
Welch, H. C. et al. P-Rex1, a PtdIns(3,4,5)P3- and Gβγ-regulated guanine-nucleotide exchange factor for Rac. Cell 108, 809–821 (2002).
Kubiseski, T. J., Culotti, J. & Pawson, T. Functional analysis of the Caenorhabditis elegans UNC-73B PH domain demonstrates a role in activation of the Rac GTPase in vitro and axon guidance in vivo. Mol. Cell. Biol. 23, 6823–6835 (2003).
Skowronek, K. R., Guo, F., Zheng, Y. & Nassar, N. The C-terminal basic tail of RhoG assists the guanine nucleotide exchange factor trio in binding to phospholipids. J. Biol. Chem. 279, 37895–37907 (2004).
Vanni, C. et al. Phosphorylation-independent membrane relocalization of ezrin following association with Dbl in vivo. Oncogene 23, 4098–4106 (2004).
Bellanger, J. M. et al. The Rac1- and RhoG-specific GEF domain of Trio targets filamin to remodel cytoskeletal actin. Nature Cell Biol. 2, 888–892 (2000).
Seipel, K., O'Brien, S. P., Iannotti, E., Medley, Q. G. & Streuli, M. Tara, a novel F-actin binding protein, associates with the Trio guanine nucleotide exchange factor and regulates actin cytoskeletal organization. J. Cell Sci. 114, 389–399 (2001).
Rumenapp, U., Freichel-Blomquist, A., Wittinghofer, B., Jakobs, K. H. & Wieland, T. A mammalian Rho-specific guanine-nucleotide exchange factor (p164-RhoGEF) without a pleckstrin homology domain. Biochem. J. 366, 721–728 (2002).
Takei, K., Slepnev, V. I., Haucke, V. & De Camilli, P. Functional partnership between amphiphysin and dynamin in clathrin-mediated endocytosis. Nature Cell Biol. 1, 33–39 (1999).
Han, J. et al. Lck regulates Vav activation of members of the Rho family of GTPases. Mol. Cell. Biol. 17, 1346–1353 (1997).
Crespo, P., Schuebel, K. E., Ostrom, A. A., Gutkind, J. S. & Bustelo, X. R. Phosphotyrosine-dependent activation of Rac-1 GDP/GTP exchange by the vav proto-oncogene product. Nature 385, 169–172 (1997). Although it had been known for years that Vav was phosphorylated, this paper describes the first instance of the activation of the nucleotide-exchange potential of a Dbl protein by phosphorylation.
Fleming, I. N., Elliott, C. M., Buchanan, F. G., Downes, C. P. & Exton, J. H. Ca2+/calmodulin-dependent protein kinase II regulates Tiam1 by reversible protein phosphorylation. J. Biol. Chem. 274, 12753–12758 (1999).
Fleming, I. N., Elliott, C. M., Collard, J. G. & Exton, J. H. Lysophosphatidic acid induces threonine phosphorylation of Tiam1 in Swiss 3T3 fibroblasts via activation of protein kinase C. J. Biol. Chem. 272, 33105–33110 (1997).
Servitja, J. M., Marinissen, M. J., Sodhi, A., Bustelo, X. R. & Gutkind, J. S. Rac1 function is required for Src-induced transformation. Evidence of a role for Tiam1 and Vav2 in Rac activation by Src. J. Biol. Chem. 278, 34339–34346 (2003).
Kiyono, M., Kaziro, Y. & Satoh, T. Induction of Rac-guanine nucleotide exchange activity of Ras-GRF1/CDC25(Mm) following phosphorylation by the nonreceptor tyrosine kinase Src. J. Biol. Chem. 275, 5441–5446 (2000).
Kesavapany, S. et al. p35/cyclin-dependent kinase 5 phosphorylation of ras guanine nucleotide releasing factor 2 (RasGRF2) mediates Rac-dependent extracellular signal-regulated kinase 1/2 activity, altering RasGRF2 and microtubule-associated protein 1b distribution in neurons. J. Neurosci. 24, 4421–4431 (2004).
Schmidt, A. & Hall, A. The Rho exchange factor Net1 is regulated by nuclear sequestration. J. Biol. Chem. 277, 14581–14588 (2002).
Tatsumoto, T., Xie, X., Blumenthal, R., Okamoto, I. & Miki, T. Human ECT2 is an exchange factor for Rho GTPases, phosphorylated in G2/M phases, and involved in cytokinesis. J. Cell Biol. 147, 921–928 (1999).
Krendel, M., Zenke, F. T. & Bokoch, G. M. Nucleotide exchange factor GEF-H1 mediates cross-talk between microtubules and the actin cytoskeleton. Nature Cell Biol. 4, 294–301 (2002).
Matsuzawa, T., Kuwae, A., Yoshida, S., Sasakawa, C. & Abe, A. Enteropathogenic Escherichia coli activates the RhoA signaling pathway via the stimulation of GEF-H1. EMBO J. 23, 3570–3582 (2004).
Michiels, F. et al. Regulated membrane localization of Tiam1, mediated by the NH2-terminal pleckstrin homology domain, is required for Rac-dependent membrane ruffling and c-Jun NH2-terminal kinase activation. J. Cell Biol. 137, 387–398 (1997).
Buchanan, F. G., Elliot, C. M., Gibbs, M. & Exton, J. H. Translocation of the Rac1 guanine nucleotide exchange factor Tiam1 induced by platelet-derived growth factor and lysophosphatidic acid. J. Biol. Chem. 275, 9742–9748 (2000).
Li, Z et al. Directional sensing requires Gβγ-mediated PAK1 and PIXα-dependent activation of Cdc42. Cell 114, 215–227 (2003). α-Pix is shown to coordinate PAK, Gβγ and Cdc42 in a molecular complex that is necessary for proper chemotaxis.
Obermeier, A. et al. PAK promotes morphological changes by acting upstream of Rac. EMBO J. 17, 4328–4339 (1998).
Zhao, Z. S., Manser, E., Loo, T. H. & Lim, L. Coupling of PAK-interacting exchange factor PIX to GIT1 promotes focal complex disassembly. Mol. Cell. Biol. 20, 6354–6363 (2000).
Park, H. S. et al. Sequential activation of phosphatidylinositol 3-kinase, βPix, Rac1, and Nox1 in growth factor-induced production of H2O2 . Mol. Cell. Biol. 24, 4384–4394 (2004).
Hussain, N. K. et al. Endocytic protein intersectin-l regulates actin assembly via Cdc42 and N-WASP. Nature Cell Biol. 3, 927–932 (2001).
Buchsbaum, R. J., Connolly, B. A. & Feig, L. A. Interaction of Rac exchange factors Tiam1 and Ras-GRF1 with a scaffold for the p38 mitogen-activated protein kinase cascade. Mol. Cell. Biol. 22, 4073–4085 (2002).
Buchsbaum, R. J., Connolly, B. A. & Feig, L. A. Regulation of p70 S6 kinase by complex formation between the Rac guanine nucleotide exchange factor (Rac-GEF) Tiam1 and the scaffold spinophilin. J. Biol. Chem. 278, 18833–18841 (2003).
Kozasa, T. et al. p115 RhoGEF, a GTPase activating protein for Gα12 and Gα13 . Science 280, 2109–2111 (1998).
Suzuki, N., Nakamura, S., Mano, H. & Kozasa, T. G Gα12 activates Rho GTPase through tyrosine-phosphorylated leukemia-associated RhoGEF. Proc. Natl Acad. Sci. USA 100, 733–738 (2003).
Hart, M. J. et al. Direct stimulation of the guanine nucleotide exchange activity of p115 RhoGEF by Gα13 . Science 280, 2112–2114 (1998). This paper was the first to describe the important physiological link between GPCR-mediated activation of Gα 13 subunits and the activation of RhoA by p115-RhoGEF. Close homologues of p115-RhoGEF behave similarly.
Chen, Z., Singer, W. D., Wells, C. D., Sprang, S. R. & Sternweis, P. C. Mapping the Gα13 binding interface of the rgRGS domain of p115RhoGEF. J. Biol. Chem. 278, 9912–9919 (2003).
Wells, C. D. et al. Mechanisms for reversible regulation between G13 and Rho exchange factors. J. Biol. Chem. 277, 1174–1181 (2002).
Biddlecome, G. H., Berstein, G. & Ross, E. M. Regulation of phospholipase C-β1 by Gq and m1 muscarinic cholinergic receptor. J. Biol. Chem. 271, 7999–8007 (1996).
Berstein, G. et al. Phospholipase C-β1 is a GTPase-activating protein for Gq/11, its physiologic regulator. Cell 70, 411–418 (1992).
Zhong, H. et al. A spatial focusing model for G protein signals. Regulator of G protein signaling (RGS) protein-mediated kinetic scaffolding. J. Biol. Chem. 278, 7278–7284 (2003).
Shamah, S. M. et al. EphA receptors regulate growth cone dynamics through the novel guanine nucleotide exchange factor ephexin. Cell 105, 233–244 (2001).
Ogita, H. et al. EphA4-mediated Rho activation via Vsm-RhoGEF expressed specifically in vascular smooth muscle cells. Circ. Res. 93, 23–31 (2003).
Lambert, J. M. et al. Tiam1 mediates Ras activation of Rac by a PI(3)K-independent mechanism. Nature Cell Biol. 4, 621–625 (2002).
Innocenti, M. et al. Mechanisms through which Sos-1 coordinates the activation of Ras and Rac. J. Cell Biol. 156, 125–136 (2002).
Cheng, L., Mahon, G. M., Kostenko, E. V. & Whitehead, I. P. Pleckstrin homology domain-mediated activation of the Rho-specific guanine nucleotide exchange factor Dbs by Rac1. J. Biol. Chem. 279, 12786–12793 (2004).
Curtis, C. et al. Scambio, a novel guanine nucleotide exchange factor for Rho. Mol. Cancer 3, 10 (2004).
Gulli, M. P. et al. Phosphorylation of the Cdc42 exchange factor Cdc24 by the PAK-like kinase Cla4 may regulate polarized growth in yeast. Mol. Cell 6, 1155–1167 (2000).
Shimada, Y., Gulli, M. P. & Peter, M. Nuclear sequestration of the exchange factor Cdc24 by Far1 regulates cell polarity during yeast mating. Nature Cell Biol. 2, 117–124 (2000).
Butty, A. C., Pryciak, P. M., Huang, L. S., Herskowitz, I. & Peter, M. The role of Far1p in linking the heterotrimeric G protein to polarity establishment proteins during yeast mating. Science 282, 1511–1516 (1998).
Butty, A. C. et al. A positive feedback loop stabilizes the guanine-nucleotide exchange factor Cdc24 at sites of polarization. EMBO J. 21, 1565–1576 (2002).
Shimada, Y., Wiget, P., Gulli, M. P., Bi, E. & Peter, M. The nucleotide exchange factor Cdc24p may be regulated by auto-inhibition. EMBO J. 23, 1051–1062 (2004).
Wiget, P., Shimada, Y., Butty, A. C., Bi, E. & Peter, M. Site-specific regulation of the GEF Cdc24p by the scaffold protein Far1p during yeast mating. EMBO J. 23, 1063–1074 (2004).
Bose, I. et al. Assembly of scaffold-mediated complexes containing Cdc42p, the exchange factor Cdc24p, and the effector Cla4p required for cell cycle-regulated phosphorylation of Cdc24p. J. Biol. Chem. 276, 7176–7186 (2001).
Boettner, B. & Van Aelst, L. The role of Rho GTPases in disease development. Gene 286, 155–174 (2002).
Turner, M. et al. A requirement for the Rho-family GTP exchange factor Vav in positive and negative selection of thymocytes. Immunity 7, 451–460 (1997).
Doody, G. M. et al. Signal transduction through Vav-2 participates in humoral immune responses and B cell maturation. Nature Immunol. 2, 542–547 (2001).
Tedford, K. et al. Compensation between Vav-1 and Vav-2 in B cell development and antigen receptor signaling. Nature Immunol. 2, 548–555 (2001).
Fujikawa, K. et al. Vav1/2/3-null mice define an essential role for Vav family proteins in lymphocyte development and activation but a differential requirement in MAPK signaling in T and B cells. J. Exp. Med. 198, 1595–1608 (2003).
O'Brien, S. P. et al. Skeletal muscle deformity and neuronal disorder in Trio exchange factor-deficient mouse embryos. Proc. Natl Acad. Sci. USA 97, 12074–12078 (2000).
Advani, A. S. & Pendergast, A. M. Bcr–Abl variants: biological and clinical aspects. Leuk. Res. 26, 713–720 (2002).
Kourlas, P. J. et al. Identification of a gene at 11q23 encoding a guanine nucleotide exchange factor: evidence for its fusion with MLL in acute myeloid leukemia. Proc. Natl Acad. Sci. USA 97, 2145–2150 (2000).
Engers, R. et al. Tiam1 mutations in human renal-cell carcinomas. Int. J. Cancer 88, 369–376 (2000).
Debily, M. A. et al. Expression and molecular characterization of alternative transcripts of the ARHGEF5/TIM oncogene specific for human breast cancer. Hum. Mol. Genet. 13, 323–334 (2004).
Malliri, A. et al. Mice deficient in the Rac activator Tiam1 are resistant to Ras-induced skin tumours. Nature 417, 867–871 (2002). Showed the importance of Tiam1 in facilitating Ras-mediated tumour formation in Tiam1-deficient mice.
Kawasaki, Y. et al. Asef, a link between the tumor suppressor APC and G-protein signaling. Science 289, 1194–1197 (2000).
Kawasaki, Y., Sato, R. & Akiyama, T. Mutated APC and Asef are involved in the migration of colorectal tumour cells. Nature Cell Biol. 5, 211–215 (2003).
Booden, M. A., Eckert, L. B., Der, C. J. & Trejo, J. Persistent signaling by dysregulated thrombin receptor trafficking promotes breast carcinoma cell invasion. Mol. Cell. Biol. 24, 1990–1999 (2004).
Pasteris, N. G. et al. Isolation and characterization of the faciogenital dysplasia (Aarskog–Scott syndrome) gene, a putative Rho/Rac guanine nucleotide exchange factor. Cell 79, 669–678 (1994).
Orrico, A. et al. Phenotypic and molecular characterisation of the Aarskog–Scott syndrome, a survey of the clinical variability in light of FGD1 mutation analysis in 46 patients. Eur. J. Hum. Genet. 12, 16–23 (2004).
Hadano, S. et al. A gene encoding a putative GTPase regulator is mutated in familial amyotrophic lateral sclerosis 2. Nature Genet. 29, 166–173 (2001).
Eymard-Pierre, E. et al. Infantile-onset ascending hereditary spastic paralysis is associated with mutations in the alsin gene. Am. J. Hum. Genet. 71, 518–527 (2002).
Gros-Louis, F. et al. An ALS2 gene mutation causes hereditary spastic paraplegia in a Pakistani kindred. Ann. Neurol. 53, 144–145 (2003).
Mahana, W., Zhao, T. M., Teller, R., Robinson, M. A. & Kindt, T. J. Genes in the pX region of human T cell leukemia virus I influence Vav phosphorylation in T cells. Proc. Natl Acad. Sci. USA 95, 1782–1787 (1998).
Fackler, O. T., Luo, W., Geyer, M., Alberts, A. S. & Peterlin, B. M. Activation of Vav by Nef induces cytoskeletal rearrangements and downstream effector functions. Mol. Cell 3, 729–739 (1999).
Zhang, H. et al. Functional interaction between the cytoplasmic leucine-zipper domain of HIV-1 gp41 and p115-RhoGEF. Curr. Biol. 9, 1271–1274 (1999).
Brugnera, E. et al. Unconventional Rac-GEF activity is mediated through the Dock180–ELMO complex. Nature Cell Biol. 4, 574–582 (2002). Provides biochemical evidence that Dock180, although lacking a DH domain, can have Rho GEF activity.
Namekata, K., Enokido, Y., Iwasawa, K. & Kimura, H. MOCA induces membrane spreading by activating Rac1. J. Biol. Chem. 279, 14331–14337 (2004).
Meller, N., Irani-Tehrani, M., Kiosses, W. B., Del Pozo, M. A. & Schwartz, M. A. Zizimin1, a novel Cdc42 activator, reveals a new GEF domain for Rho proteins. Nature Cell Biol. 4, 639–647 (2002).
Shinohara, M. et al. SWAP-70 is a guanine-nucleotide-exchange factor that mediates signalling of membrane ruffling. Nature 416, 759–763 (2002).
Mavrakis, K. J., McKinlay, K. J., Jones, P. & Sablitzky, F. DEF6, a novel PH–DH-like domain protein, is an upstream activator of the Rho GTPases Rac1, Cdc42, and RhoA. Exp. Cell Res. 294, 335–344 (2004).
Hardt, W. D., Chen, L. M., Schuebel, K. E., Bustelo, X. R. & Galan, J. E. S. typhimurium encodes an activator of Rho GTPases that induces membrane ruffling and nuclear responses in host cells. Cell 93, 815–826 (1998). Shows that bacteria possess unique proteins that function as RhoGEFs to facilitate their invasion of human host cells.
Friebel, A. et al. SopE and SopE2 from Salmonella typhimurium activate different sets of RhoGTPases of the host cell. J. Biol. Chem. 276, 34035–34040 (2001).
Margarit, S. M. et al. Structural evidence for feedback activation by Ras·GTP of the Ras-specific nucleotide exchange factor SOS. Cell 112, 685–695 (2003).
Katoh, H. & Negishi, M. RhoG activates Rac1 by direct interaction with the Dock180-binding protein Elmo. Nature 424, 461–464 (2003).
Kaartinen, V. et al. Abnormal function of astroglia lacking Abr and Bcr RacGAPs. Development 128, 4217–4227 (2001).
Kaartinen, V., Nagy, A., Gonzalez-Gomez, I., Groffen, J. & Heisterkamp, N. Vestibular dysgenesis in mice lacking Abr and Bcr Cdc42/RacGAPs. Dev. Dyn. 223, 517–525 (2002).
Voncken, J. W. et al. Increased neutrophil respiratory burst in bcr-null mutants. Cell 80, 719–728 (1995).
Hirsch, E. et al. Defective dendrite elongation but normal fertility in mice lacking the Rho-like GTPase activator Dbl. Mol. Cell. Biol. 22, 3140–3148 (2002).
Brambilla, R. et al. A role for the Ras signalling pathway in synaptic transmission and long-term memory. Nature 390, 281–286 (1997).
Giese, K. P. et al. Hippocampus-dependent learning and memory is impaired in mice lacking the Ras-guanine-nucleotide releasing factor 1 (Ras-GRF1). Neuropharm. 41, 791–800 (2001).
Font de Mora, J. et al. Ras-GRF1 signaling is required for normal β-cell development and glucose homeostasis. EMBO J. 22, 3039–3049 (2003).
Fernandez-Medarde, A. et al. Targeted disruption of Ras-Grf2 shows its dispensability for mouse growth and development. Mol. Cell. Biol. 22, 2498–2504 (2002).
Wang, D. Z. et al. Mutation in Sos1 dominantly enhances a weak allele of the EGFR, demonstrating a requirement for Sos1 in EGFR signaling and development. Genes Dev. 11, 309–320 (1997).
Qian, X. et al. The Sos1 and Sos2 Ras-specific exchange factors: differences in placental expression and signaling properties. EMBO J. 19, 642–654 (2000).
Esteban, L. M. et al. Ras-guanine nucleotide exchange factor sos2 is dispensable for mouse growth and development. Mol. Cell. Biol. 20, 6410–6413 (2000).
Zhang, R., Alt, F. W., Davidson, L., Orkin, S. H. & Swat, W. Defective signalling through the T- and B-cell antigen receptors in lymphoid cells lacking the vav proto-oncogene. Nature 374, 470–473 (1995).
Tarakhovsky, A. et al. Defective antigen receptor-mediated proliferation of B and T cells in the absence of Vav. Nature 374, 467–470 (1995).
Fischer, K. D. et al. Defective T-cell receptor signalling and positive selection of Vav-deficient CD4+ CD8+ thymocytes. Nature 374, 474–477 (1995).
Acknowledgements
We would like to apologize for not being able to cite original work of many colleagues due to space constraints. Our studies are supported by grants to C.J.D. and to J.S from the National Institutes of Health. K.L.R. was supported by a fellowship from the National Cancer Institute.
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Glossary
- G-PROTEIN-COUPLED RECEPTOR
-
A seven-helix membrane-spanning cell-surface receptor that signals through heterotrimeric GTP-binding and -hydrolysing G proteins to stimulate or inhibit the activity of a downstream enzyme.
- PHAGOCYTOSIS
-
An actin-dependent process by which cells engulf external particulate material by extension and fusion of pseudopods.
- CYTOKINESIS
-
The separation of a cell into two, which is marked by ingression of the cleavage 'furrow' between two segregated masses of genomic DNA.
- PLECKSTRIN HOMOLOGY (PH) DOMAIN
-
A sequence of ∼100 amino acids that is present in many signalling molecules and that binds to lipid products of phosphatidylinositol 3-kinase. Pleckstrin is a protein of unknown function that was originally identified in platelets. It is a principal substrate of protein kinase C.
- SWITCH REGIONS
-
Regions of nucleotide-binding proteins that have different conformations in the triphosphate-bound, compared to the diphosphate-bound, state.
- α-HELIX
-
An element of protein secondary structure in which hydrogen bonds that lie along the backbone of a single polypeptide cause the chain to form a right-handed helix.
- 310 HELIX
-
A tighter, less stable helix than the α-helix, with three residues per turn, which form hydrogen-bonded loops of 10 atoms.
- HOMOLOGY MODELLING
-
Prediction of the tertiary structure of an unknown protein using a known three-dimensional structure of a homologous protein.
- CLEAVAGE FURROW
-
An invagination of the plasma membrane in the division plane of an animal cell that contains a contractile ring, and that leads to scission of the daughter cells.
- CHEMOTAXIS
-
A type of migration that is stimulated by a gradient of a chemical stimulant or chemoattractant.
- SCAFFOLD
-
A protein that functions as a support to assemble a multiprotein complex.
- SRC-HOMOLOGY-3 (SH3) DOMAIN
-
A protein module of ∼80 amino acids that is present in a range of proteins and that was first identified in the protein kinase Src. SH3 domains interact with proline-rich sequences that usually contain a PXXXPXR motif (where X is any amino acid).
- PDZ DOMAIN
-
(Postsynaptic-density protein of 95 kDa, Discs large and Zona occludens-1). A region that is present in several scaffolding proteins and that is named after the founding members of this protein family. PDZ domains bind to specific short amino-acid sequences that are found in several proteins at, or outside, junctions.
- HETEROTRIMERIC G PROTEIN
-
A complex of three proteins (Gα, Gβ and Gγ). Whereas Gβ and Gγ form a tight complex, Gα is part of the complex in its inactive, GDP-bound, form but dissociates in its active, GTP-bound, form. Both Gα and Gβγ can transmit downstream signals after activation.
- GROWTH CONE
-
Motile tip of the axon or dendrite of a growing nerve cell, which spreads out into a large cone-shaped appendage.
- BUD SITES
-
Cell-wall sites where the yeast S. cerevisiae undergoes reproduction by initiation of budding.
- MATING PROJECTION
-
A specialized structure that is formed by vegetative S. cerevisiae to initiate polarized cell growth, and to allow polarized mating cells to signal to one another.
- DOMINANT NEGATIVE
-
A defective protein that retains interaction capabilities and so distorts or competes with normal proteins.
- EXPRESSION-LIBRARY SCREENS
-
A genome-wide cloning strategy that uses a biological gain-of-function (for example, uncontrolled growth) to isolate and identify genes with specific cellular activities.
- C2 DOMAIN
-
Better known as Ca2+-dependent phospholipid-binding domains in proteins such as conventional protein kinase C isoforms and synaptotagmin. The C2 domain is another modular signalling domain that can induce membrane–protein, or protein–protein, interactions, after binding several Ca2+ ions. There are C2 domains that do not bind Ca2+ but constitutively bind to a membrane, others that might be involved in Ca2+-independent protein–protein interactions, and some that might bind inositol polyphosphates.
- ARMADILLO (ARM) ARRAY
-
The armadillo repeat is an ∼40-amino-acid-long tandemly repeated sequence motif that was first identified in the Drosophila melanogaster segment polarity gene armadillo.
- SQUAMOUS CELL CARCINOMA
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A carcinoma that develops from the layers of thin, flat squamous cells of the epithelium.
- CALPONIN-HOMOLOGY DOMAIN
-
A protein domain, which is often found tandemly arrayed, that functions in the binding of actin.
- CYTOPATHICITY
-
The ability of certain viruses to cause degenerative changes in their host cells as a consequence of viral invasion and multiplication. This might include changes in cell morphology, cell lysis, cell death and altered cell–cell interactions.
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Rossman, K., Der, C. & Sondek, J. GEF means go: turning on RHO GTPases with guanine nucleotide-exchange factors. Nat Rev Mol Cell Biol 6, 167–180 (2005). https://doi.org/10.1038/nrm1587
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DOI: https://doi.org/10.1038/nrm1587