D. BOULTER and B. PARTHIER At the time of the former edition of the Encyclopedia of Plant Physiology, approximately 25 years ago, no complete plant protein amino acid sequences or nucleic acid sequences had been determined. Although the structure of DNA and its function as the genetic material had just been reported, little detail was known of the mechanism of its action, and D. G. CATCHSIDE was to write in the first chapter of the first volume of the Encyclopedia: "There is a consider able body of evidence that the gene acts as a unit of physiological action through the control of individual enzymes". No cell-free transcription and pro tein-synthesizing systems were available and the whole range of powerful meth ods of recombinant DNA technology was still to be developed. Today for the first time with plant systems, it is possible not only to describe their molecular biology but also to manipulate it, i. e. , to move from a description to a technological phase. The properties of living systems are inscribed by those of the proteins and nucleic acids which they synthesize. Proteins, due to their very large size, occur as macromolecules in colloidal solution or associated in supra-molecular colloi dal form. The colloidal state confers low thermal conductivity, low diffusion coefficients and high viscosity, properties which buffer a biological system from the effects of a changing environment. Biological systems not only have great stability, but also the capacity to reproduce.

With contributions by numerous experts

Part 2=Volume 14B.

With contributions by numerous experts

During the summer of 1974 we discussed the state of molecular biology and biochemical developmental biology in plants on a few occasions in Paris and in Strasbourg. The number of laboratories engaged in such research is minute compared with those studying comparable problems in animal and bacterial systems, but by then much interesting work had been done and a great momentum was building. It seemed to us that the summer of 1976 would be a good time to review these areas of plant biology for students as well as advanced workers. We outlined a program for a course to colleagues both in Europe and the United States and asked a few potential lecturers if they would be interested. The response was not just positive; it was overwhelm ingly enthusiastic. Those who had some acquaintance with Alsace, and especially with Strasbourg, invariably told us that they had two reasons for being enthusiastic about participating - the subject and the proposed site. The lectures published here* reflect the diversity of current research in plant molecular biology and biochemical developmental biology. Each lecture gives us a glimpse of the depth of questions being asked, and sometimes answered, in segments of this field of investigation. This research is directed at fundamental biological problems, but answers to these questions will provide knowledge essential for bringing about major changes in the way the world's agricultural enterprise can be improved.

This book provides both in-depth background and up-to-date information in this area. The chapters are organized by general themes and principles, written by experts who illustrate topics with current findings. Topics covered include: - the role of ions and hydration in protein-nucleic acid interactions - transcription factors and combinatorial specificity - indirect readout of DNA sequence - single-stranded nucleic acid binding proteins - nucleic acid junctions and proteins, - RNA protein recognition - recognition of DNA damage. It will be a key reference for both advanced students and established scientists wishing to broaden their horizons.