Jos A.F. Op den Kamp - Böcker

The meeting on "Molecular Mechanisms of Lipid and Protein Traffic", sponsored by NATO Scientific Affairs Division as an Advanced Study Institute and by the Federation of European Biochemical Societies as a Lecture Course was held in Cargese, France, in June 1997. The program included introductory lectures, specialized up-to-date contributions, poster sessions, tutorials and workshops. Emphasis was laid on the new developments in the field of membrane dynamics, in particular on the insertion and translocation of proteins; on intracellular protein, lipid and membrane traffic and sorting and on the mutual interactions between the various events occurring during membrane biogenesis. Mitochondrial biogenesis, chloroplast assembly and the insertion of proteins into peroxisomes were highlighted. Much progress in these research areas has been made in recent years and the ASI provided an excellent opportunity to illustrate this progress in comparison with previous meetings on a similar topic. Not only graduate students and postdocs took advantage from this program but also experienced scientists were given the opportunity to obtain a complete overview of recent progress and the remodeling of ideas and concepts.

Many individual aspects of the dynamics and assembly of biological membranes have been studied in great detail. Cell biological approaches, advanced genetics, biophysics and biochemistry have greatly contributed to an increase in our knowledge in this field.lt is obvious however, that the three major membrane constituents - lipids, proteins and carbohydrates- are studied, in most cases separately and that a coherent overview of the various aspects of membrane biogenesis is not readily available. The NATO Advanced Study Institute on "New Perspectives in the Dynamics of Assembly of Biomembranes" intended to provide such an overview: it was set up to teach students and specialists the achievements obtained in the various research areas and to try and integrate the numerous aspects of membrane assembly into a coherent framework. The articles in here reflect this. Statting with detailed contributions on phospholipid structure, dynamics, organization and biogenesis, an up to date overview of the basic, lipidic backbone of biomembranes is given. Extensive progress is made in the research on membrane protein biosynthesis. In particular the post- and co-translational modification processes of proteins, the mechanisms of protein translocation and the sorting mechanisms which are necessary to direct proteins to their final, intra - or extracellular destination have been characterized in detail. Modern genetic approaches were indispensable in this research area: gene cloning, hybrid protein construction, site directed mutagenesis and sequencing techniques elucidated many functional aspects of specific nucleic acid and amino acid sequences.

The Advanced Study Institute on "Structure, Biogenesis and Dynamics of Biological Membranes, held in Cargese from June 14-26, 1993, has been dealing with four major topics in membrane biochemistry today: lipid dynamics and lipid-protein interactions, protein translocation and insertion, intracellular traffic aud protein structure and folding. The lecturers discussed these topics starting from several disciplines, including biochemistry, cell biology, genetics, and biophysics. This wayan interdisciplinary and very inte~sting view on biological membrane systems was obtained. At first an extensive overview of -mainly biophysical -techniques which can be used to study dynamic processes in membranes was presented. Sophisticated approaches such as ESR and NMR have been applied succesfully to unravel details of specific lipid-protein interactions. x­ ray analysis provides detailed structural information of several proteins and the possible implications for protein functions. Information obtained this way is complemented by studies on mechanisms and kinetics of protein folding. The latter information is indispensable when discussing protein translocation and insertion: proces:;es in which folding and unfolding play essential roles. Extensive insight was offered in the complicated machinery of phospholipid biosynthesis. In particular, the application of sophisticated genetic techniques has allowed a better understanding of the mechanisms regulating the synthetic machinery and detailed studies on a variety of mutants, lacking one or more of the essential enzymes, have resulted in the beginning of a bL!: