Book excerpt: 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.