Recent advances in molecular biology have shown GTPases and phosphoproteins to be the paramount molecular switches uti- lized intracellularly in biological systems. The origins of the GTPase switch appear to be almost as ancient as life it- self, 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 ac- curacy 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 t h e reference work for GTPases.

Inhalt
Section IV: Signal Transduction by Trimeric G Proteins.- A. Cellular Architecture and its Role in Signal Transduction.- 44 G-Proteins Have Properties of Multimeric Proteins: An Explanation for the Role of GTPases in their Dynamic Behavior.- B. G-Protein Coupled Receptors.- 45 The Superfamily: Molecular Modelling.- 46 The Role of Receptor Kinases and Arrestin-Like Proteins in G-Protein-Linked Receptor Desensitization.- C. Trimeric G-Proteins.- 47 Qualitative and Quantitative Characterization of the Distribution of G-Protein ? Subunits in Mammals.- 48 Subunit Interactions of Heterotrimeric G-Proteins.- 49 G-Protein ? Subunit Chimeras Reveal Specific Regulatory Domains Encoded in the Primary Sequence.- 50 The GTPase Cycle: Transducin.- 51 Transcriptional, Posttranscriptional, and Posttranslational Regulation of G-Proteins and Adrenergic Receptors.- 52 G-Protein Subunit Lipidation in Membrane Association and Signaling.- 53 Phosphorylation of Heterotrimeric G-Protein.- 54 Receptor to Effector Signaling Through G-Proteins: ?? Dimers Join ? Subunits in the World of Higher Eukaryotes.- D. Effectors of G-Proteins.- 55 Molecular Diversity of Mammalian Adenylyl Cyclases: Functional Consequences.- 56 The Light-Regulated cGMP Phosphodiesterase of Vertebrate Photoreceptors: Structure and Mechanism of Activation by Gt?.- 57 High-Voltage Activated Ca2+ Channel.- 58 Phospholipase C-? Isozymes Activated by G?q Members.- 59 Stimulation of Phospholipase C by G-Protein ?? Subunits.- E. Specialized Systems.- 60 Rhodopsin/G-Protein Interaction.- 61 Fast Kinetics of G-Protein Function In Vivo.- 62 The Yeast Pheromone Response G-Protein.- 63 Ga Proteins in Drosophila: Structure and Developmental Expression.- 64 Signal Transduction by G-Proteins in Dictyostelium discoideum.- 65Functional Expression of Mammalian Receptors and G-Proteins in Yeast.- 66 G-Proteins in the Signal Transduction of the Neutrophil.- 67 Hormonal Regulation of Phospholipid Metabolism via G-Proteins: Phosphoinositide Phospholipase C and Phosphatidylcholine Phospholipase D.- 68 Hormonal Regulation of Phospholipid Metabolism via G-proteins II: PLA2 and Inhibitory Regulation of PLC.- 69 G-Protein Regulation of Phospholipase C in the Turkey Erythrocyte.- 70 Hormonal Inhibition of Adenylyl Cyclase by ?i and?? ?i or ?? ?i and/or ??.- 71 Neurobiology of Go.- 72 Involvement of Pertussis-Toxin-Sensitive G-Proteins in the Modulation of Ca2+ Channels by Hormones and Neurotransmitters.- 73 Regulation of Cell Growth and Proliferation by Go.- 74 Role of Nucleoside Diphosphate Kinase in G-Protein Action.- 75 G-Protein Regulation of Cardiac K+ Channels.- 76 Modulation of K+ Channels by G-Proteins.- 77 ATP-Sensitive K+ Channel: Properties, Occurrence, Role in Regulation of Insulin Secretion.- 78 Modulation of Maxi-Calcium-Activated K Channels: Role of Ligands, Phosphorylation, and G-Proteins.- 79 Regulation of the Endosomal Proton Translocating ATPase (H+-ATPase) and Endosomal Acidification by G-Proteins.- 80 cAMP-Independent Regulation of Adipocyte Glucose Transport Activity and Other Metabolic Processes by a Complex of Receptors and their Associated G-Proteins.- References.