Current Topics in Cellular Regulation, Volume 10 presents the fundamental mechanisms involved in the regulation of diverse cellular activities, including cellular differentiation, intermediary metabolism, and the transfer of genetic information. This book provides information pertinent to the various aspects of cellular regulation.Organized into six chapters, this volume begins with an overview of the enzymes that exhibit half-of-the-sites activity. This text then examines the two different aspects of cyclic AMP-mediated systems. Other chapters consider the possible role of citrate synthase in the regulation of the citric acid cycle. This book discusses as well the regulation of the pentose phosphate pathway. The final chapter reviews the evidence for the occurrence of futile cycles at three control points in the metabolism of glucose, namely, at the level of glucose phosphorylation, at the interconversion of fructose mono- and biophosphates, and between pyruvate and phosphenol pyruvate.This book is a valuable resource for biochemists, biologists, and research workers.

List of ContributorsPrefacePreface to Volume 10Contents of Previous VolumesThe Role of Negative Cooperativity and Half-of-the-Sites Reactivity in Enzyme Regulation I. Introduction II. Theoretical III. Negatively Cooperative Enzymes-Examples IV. Mixed Negative-Positive Cooperativity V. Half-of-the-Sites Reactivity VI. Enzymes with Half-of-the-Sites Reactivity VII. Evaluation of Negative Cooperativity and Half-of-the-Sites Reactivity VIII. The Biological Significance of Negative Cooperativity ReferencesSignal Transfer from Hormone Receptor to Adenylate Cyclase I. Introduction II. Hormone-Receptor Interactions III. Adenylate Cyclase IV. Coupling Between Receptor and Adenylate Cyclase V. Concluding Remarks References Addendum References for AddendumRegulation of the Glycogen Phosphorylase System-From Physical Measurements to Biological Speculations I. Introduction II. The Phosphorylase Cascade System III. The Individual Components of the Cascade System IV. The Methods V. Effects of Ligands on Phosphorylase VI. Heterotropic Interactions of Phosphorylase b VII. The Relation Between Ligand and Probe Binding Sites VIII. The Phosphorylase b to a Conversion IX. Protein-Glycogen Complexes-An Approach to the in Vivo Situation X. The Control of Phosphorylase Activity in Vivo XI. Conclusion ReferencesCitrate Synthase I. Introduction II. Molecular Properties III. Ionic Effects IV. Regulation of Activity-The in Vitro Behavior V. Regulation of Activity-Approaches to the in Vitro Behavior VI. Chemistry of the Catalytic and Regulatory Sites VII. Concluding Remarks ReferencesDefects of Glucose 6-Phosphate and 6-Phosphogluconate Dehydrogenases in Neurospora and Their Pleiotropic Effects I. Introduction II. Mutants III. Glucose-6-Phosphate Dehydrogenase IV. 6-Phosphogluconate Dehydrogenase V. Conclusions from Enzyme Studies VI. Pleiotropic Effects of Pentose Monophosphate Shunt Lesions VII. Summary ReferencesFutile Cycles in the Metabolism of Glucose I. Introduction II. Isotopic Reversibility in the Gluconeogenic Pathway III. The Fate of Glucose Hydrogens in Glycolysis IV. Evaluation of Recycling with Tritium-Labeled Glucoses in Liver V. Metabolism of Labeled Glucose by Rat Liver VI. Recycling Between Pyruvate and Phosphoenol Pyruvate VII. Recycling of Fructose 6-Phosphate and Thermogenesis VIII. Occurrence of Other Futile Cycles IX. Recycling of Glucose in Vivo X. The Role of Futile Cycles in the Control of Glucose Metabolism XI. Concluding Remarks ReferencesSubject Index