Discovered and first isolated in 1966 in C. De Duve's laboratory, peroxisomes - organelles which are present in nearly all eukaryotic cells - are still not fully understood. More than 40 peroxisomal enzymes catalyzing a variety of reactions have been characterized. Moreover, peroxisomes can be regarded as toxicological indicators: several compounds, including hypolipemic drugs, plasticizers or pesticides trigger their proliferation. This proliferation may lead to hepatocarcinogenesis in rodents. Interest in peroxisomes stems not only fromtheir biology, but also because there is a deficiency of peroxisomal functions in several genetic diseases. Some genes involved in inborn errors of peroxisomal function have recently been identified. In this manual, based on a FEBS Advanced Course on peroxisomes, protocols on the following topics are described in detail: Isolation and characterization of peroxisomes by ultracentrifugationand immunoblotting; gene regulation studied by mRNA isolation, hybridizationand DNA cell transfection; use of cell lines as peroxisome proliferator targets; transformation with retrovirus; peroxisomes as toxicological markers; cytochrome P450 induction; drug design and computer analysis of ligand/receptor interaction involved in peroxisomal gene expression.

This manual on "Dynamics of Membrane Proteins and Cellular Energetics" is the result of a FEBS-CNRS Course held in Grenoble and Besanc;{on in September 1987.' It appears to be, after the first, published in 1979 the fifth of the series. After focussing on the "Biochemistry of Membranes" (1979) it was the turn of "Membrane Proteins" (1981) and of Enzymes, Receptors and Carriers of Biological Membranes (1983), fo1- wed by "Membrane Proteins Isolation and Characterization" ( 1986) . Al though the central issue has always been the its components and its functions, each biological membrane, manual has put the accent on somewhat different issues corresponding to the most innovative, interesting research in the field. After almost a decade this new manual appears, which stresses the aspect of the integration of membrane research at a cellular level. Such a novel emphasis is the consequence of the common interest of cell biology and biochemistry to understand the results of the biochemical analysis of membrane proteins in the context of the cell complexity. Consequently most of the experimental protocols are dealing with cellular models, but with clear reference to the function and structure of isolated membrane proteins.