Recent advances in molecular biology have shown GTPases and phosphoproteins to be the paramount molecular switches utilized intracellularly in biological systems. The origins of the GTPase switch appear to be almost as ancient as life itself, and through evolution nature has adapted this switch to a variety of purposes. In this two-volume work a broad survey of the major classes of GTPases is presented. The role of GTPases in ensuring accuracy during protein translation, a new look at the trimeric G-protein cycle, the molecular function of ARF in vesicle coating, the emerging role of the dynamin family in vesicle transfer, GTPases which activate GTPases during nascent protein translocation, and the many roles of ras-related proteins in growth, cytoskeletal polymerization, and vesicle transfer, are all described in 80 chapters by the leading authorities in their fields. Both detailed knowledge of specific systems or proteins and general principles of structure and function are offered. Much of this information has never been published before. At the rate the extended family of GTPases is growing it becomes increasingly unlikely that we will again get it to sit for a group portrait such as this. Therefore, the volume has the chance to become the reference work for GTPases.

Table of Contents:
Section I: Biological Importance of GTPase-Driven Switches.- 1 GTPases Everywhere!.- 2 Proofreading in the Elongation Cycle of Protein Synthesis.- 3 A New Look at Receptor-Mediated Activation of a G-Protein.- 4 Small GTPases and Vesicle Trafficking: Sec4p and its Interaction with Up- and Downstream Elements.- 5 Cytoskeletal Assembly: The Actin and Tubulin Nucleotidases.- 6 Dynamin, A Microtubule-Activated GTPase Involved in Endocytosis.- 7 Transmembrane Protein Translocation: Signal Recognition Particle and Its Receptor in the Endoplasmic Reticulum.- 8 GTPases and Actin as Targets for Bacterial Toxins.- Section II. Structure of the GTPase Switches.- 9 Eukaryotic Translation Factors Which Bind and Hydrolyze GTP.- 10 Heterotrimeric G-Proteins: ?, ?, and ? Subunits.- 11 Molecular Diversity in Signal Transducing G-Proteins.- 12 Structural Conservation of Ras-Related Proteins and Its Functional Implications.- 13 Conformational Switch and Structural Basis for Oncogenic Mutations of Ras Proteins.- 14 Structural and Mechanistic Aspects of the GTPase Reaction of H-ras p21.- 15 Analysis of Ras Structure and Dynamics by Nuclear Magnetic Resonance.- 16 Molecular Dynamics Studies of H-ras p21-GTP.- Section III: Small Ras — Related GTPases.- A. Control of Growth and Differentiation by the Ras Family.- 17 The Discovery of Ras and Its Biological Importance.- 18 Oncogenic Activation of ras Proteins.- 19 Dominant Inhibitory Ras Mutants: Tools for Elucidating Ras function.- 20 The Involvement of Cellular ras in Proliferative Signaling.- 21 Regulation of Ras-Interacting Proteins in Saccharomyces cerevisiae.- 22 Lipid Modifications of Proteins in the Ras Superfamily.- 23 GTPase Activating Proteins.- 24 Guanine Nucleotide Dissociation Stimulators.- 25 The Biology of Rap.- B. VesicleTransfer/Vesicle Fusion.- 26 GTPases and Interacting Elements in Vesicle Budding and Targeting in Yeast.- 27 Ypt Proteins in Yeast and Their Role in Intracellular Transport.- 28 Compartmentalization of rab Proteins in Mammalian Cells.- 29 GTPases in Transport Between Late Endosomes and the Trans Golgi Network.- 30 Endocytic Function in Cell-Free System.- 31 Synaptic Vesicle Membrane Traffic and the Cycle of Rab3.- 32 Regulated Exocytosis and Interorganelle Vesicular Traffic: A Comparative Analysis.- 33 Regulated and Constitutive Secretion Studied In Vitro: Control by GTPases at Multiple Levels.- 34 The Biology of ADP-Ribosylation Factors.- 35 Molecular Characterization of ADP-Ribosylation Factors.- C. rho and rho-Like Proteins.- 36 rho and rho-Related Proteins.- 37 The Mammalian Homolog of the Yeast Cell-Division-Cycle Protein, CDC42: Evidence for the Involvement of a Rho-Subtype GTPase in Cell Growth Regulation.- D. Regulation of and by Small GTPases.- 38 Role of Rap1B and Its Phosphorylation in Cellular Function: A Working Model.- 39 GDP/GTP Exchange Proteins for Small GTP-Binding Proteins.- 40 GTP-Mediated Communication Between Intracellular Calcium Pools.- 41 Coupling of ras to the T Cell Antigen Receptor.- 42 GTPases as Regulators of Regulated Secretion.- 43 ADP-Ribosylation of Small GTPases by Clostridium botulinum Exoenzyme C3 and Pseudomonas aeruginosa Exoenzyme S.