Current interest in NAD (Nicotinamide adenine dinucleotide) in biological systems focuses on its role in ADP-ribose transfer reactions. These appear to be fundamentally involved in the regulation of many physiological processes. The contributions in this monograph thus represent the range of research in the very active investigation of niacin metabolism. The major topics covered are: ??? - Enzymology of ADP-Ribosylation - ADP-Ribosylation and Chromatin Function - Carcinogenesis and Differentiation - NAD Metabolism and Chemotherapy - ADP-Ribosylation and Signal Transduction - Molecular Genetic Approaches to ADP-RibosylationCurrent interest in NAD (Nicotinamide adenine dinucleotide) in biological systems focuses on its role in ADP-ribose transfer reactions. These appear to be fundamentally involved in the regulation of many physiological processes. The contributions in this monograph thus represent the range of research in the very active investigation of niacin metabolism. The major topics covered are: ??? - Enzymology of ADP-Ribosylation - ADP-Ribosylation and Chromatin Function - Carcinogenesis and Differentiation - NAD Metabolism and Chemotherapy - ADP-Ribosylation and Signal Transduction - Molecular Genetic Approaches to ADP-RibosylationOne: Enzymology of ADP-Ribosylation.- Amino Acid-Specific ADP-Ribosylation: Purification and Properties of an Erythrocyte ADP-Ribosylarginine Hydrolase.- ADP-Ribosyltransferase and Endogenous Acceptor Proteins in Animal Muscle Tissues: ADP-Ribosylation of Ca2+-Dependent ATPase in Rabbit Skeletal Muscle Sarcoplasmic Reticulum and the Effect of Basic Peptides.- Endogenous ADP-Ribosylation of Proteins at Cysteine Residues.- Reversible ADP-Ribosylation of Dinitrogenase Reductase from Rhodospirillum rubrum Regulates the Activity of the Enzyme In Vivo and In Vitro.- Phospho ADP-Ribosylation and Phospho Adenylylation of Proteins.- ADP-Ribosyl Transferase of Mitochondria and of Ribonucleoprotein Particles Containing Silent Messenger RNA.-l£*