This volume is the second part of the book on "Chromatin Structure and Function", which resulted from a NATO-Advanced Study Institute held at Erice during April 1978. In addition to giving an updated and detailed description of various levels of chromatin organization, i. e. octamers, nucleosomes, multimers, solenoid and higher order fibers (including the most recent, yet unpublished, findings), it focuses, in a tutorial and organic format, on the possible mechanisms controlling transcription and on the basic biological phenomena (either genetic or epigenetic) related to cell aging, cell cycle, differentiation, transformation and chemical carcinogenesis. The most significant (sometime spirite~ discussion sessions have been included at the end of every section. Their clarifying nature is further supported by the final section (V), which summarizes and reviews the current state of the art on the genetic apparatus and its constituents. All chapters have selected up-to-date references; quite a few have an extensive bibliography both in terms of basic reference books and most recent findings. A few chapters, dealing at the level of intact cell and/or in classical genetic terms, with aging, differentiation and neoplastic transformation, have been included to furnish a more comprehensive view of fundamental cell functions directly and indirectly related to the structure and function of the genetic apparatus. At the same time it is hoped that interested students and investigators will find in the chapters of this volume the necessary and stimulating introduction to the wide variety of fundamental mechanism and phenomena occurring in higher eukaryotes.

Inhalt
of Part A.- Section I: What is the Chromatin?.- Properties and Composition of Isolated Chromatin.- Expressed and Nonexpressed Portions of the Genome: Their Separation and Their Characterization.- Discussion.- Section II: Physical, Chemical and Biological Techniques for Studying Nucleosome, Chromatin, Chromosome and Nuclei.- Electron Microscopy: A Tool for Visualizing Chromatin.- Transcriptional Control of Native Chromatin.- Circular Dichroism of DNA, Protein and Chromatin.- Important Hydrodynamic and Spectroscopic Techniques in the Field of Chromatin Structure.- Preparation and Analysis of Core Particles and Nucleosomes: A Conveinient Method For Studying the Protein Composition of Nucleosomes Using Protamine-Release into Triton-Acid-Urea Gels.- The Interaction of Histones with DNA: Equilibrium Binding Studies.- Nucleosome Shape and Structure in Solution from Flow Birefringence.- Scattering and Diffraction by Neutrons and X-rays in the Study of Chromatin.- Nuclear Magnetic Resonance Studies of Nucleic Acids and Proteins.- Techniques for Cytochemical Studies of the Nucleus and its Substructures.- Chromatin Study in Situ: I. Image Analysis.- Chromatin Study in Situ: II. Static and Flow Microfluorimetry.- Chromatin Study in Situ: III. Differential Effects of Feulgen Hydrolysis.- Scanning and Flow Photometry of Chromosomes.- Discussion.- Section III: Various Levels of Chromatin Organization and Mechanisms for Transcriptional Control.- Histones Assembly and Their Structural Role for Nucleosome Core.- Nuclease Digestion and the Structure of Chromatin.- Reconstitution of Nucleosomes.- Conformation of Polynucleosomes in Low Ionic Strength Solution.- Chromatin Structure: Relation of Nucleosomes of DNA Sequences.- Histone Complexes, Nucleosomes, Chromatin and Cell-Cycle DependentModification of Histones.- Evidence for Superstructures of Wet Chromatin.- Chromatin Fractionation and the Properties of Transcriptionally Active Regions of Chromatin.- Chromatin Reconstitution and Non-Histone Proteins.- Discussion.- Section IV: Structure-Function of the Genetic Apparatus and Cell Cycle, Aging, Neoplastic Transformation, Differentiation, Chemical Carcinogenesis.- The Structure and Function of Chromatin in Lower Eukaryotes.- Chromatin Structure from Angstrom to Micorn Levels, and Its Relationship to Mammalian Cell Proliferation.- Chromatin Pattern in Situ: Dependence upon Cell Cycle, Preimplantation and Development, and Cellular Aging in Vitro.- Neoplastic Transformation: The Relevance of in Vitro Studies for the Understanding of Tumor Pathenogenesis and Neoplastic Growth.- Cell Differentiation and Malignancy in Leukemia.- Cellular Morphometry in Transformation, Differentiation and Aging.- Basic Mechanisms in Chemical Carcinogenesis.- Carcinogen Induced Alteration in Gene Packing and Its Possible Significance in Carcinogenesis.- Covalent Binding of a Carcinogen to DNA as a Probe of Chromatin Structure.- Carcinogenesis, DNA Repair and Chromatin.- Electromagnetic Induction of Electrochemical Information at Cell Surfaces: Application to Chromatin Structure Modification.- Discussion.- Section V: Review and Summary of the Genetic Apparatus.- Session I: Basic Components of the Genetic Apparatus.- Session II: The Second Level of Organization Chromatin.- Session III: The Third Level of Organization.- Session IV: Generalized Biological Effects.