Christopher Redfern brings together in Retinoid Protocols a comprehensive collection of key biochemical and molecular methods for retinoid research. These easily reproducible techniques range from methods of handling and analyzing retinoids to advanced protocols for gene targeting, from binding protein function in transgenic animals to the study of nuclear retinoid receptors. In addition, the book makes accessible to all retinoid researchers such advanced techniques as cloning via RT-PCR, fluorimetry methods, recombinant protein purification and characterization, the use of antisense oligonucleotides to study the role of CRABPs, immunological and in situ hybridization methods, photoaffinity labeling, gel-shift analysis, and differential display.

Many of the chapters in Retinoid Protocols represent landmarks in retinoid methodology because they give step-by-step instructions for techniques central to understanding cellular control by retinoids. These indispensable techniques will be fundamental for all those working with retinoids, and so will play a key role in the development of new drugs and therapies for treating human disease.

Interest in retinoic acid, the main biologically active derivative of vi- min A or retinol, increased dramatically between 1989 and 1993, following the cloning of nuclear receptors or RARs reported in 1987 (Fig. 1). Important discoveries since then have shown how RARs work as all-trans retinoic ac- dependent heterodimers with related nuclear receptors for 9-cis retinoic acid called RXRs. This has stimulated the development of synthetic analogs s- cific for each type of receptor, and opens the way to develop new methods for regulating pharmacologically the activity ofretinoic acid-dependent pathways of gene activation. The potential for the development of new drugs by the pharmaceutical industry is now a maj or factor driving forward our understa- ing of vitamin A-regulated pathways in animal development and homeostasis. However, apart from the real potential ofretinoid analogs as novel pharma- logical agents, there remains the considerable intellectual challenge of und- standing the way in which vitamin A and its derivatives function in cell development and differentiation. Retinoid Protocols is an attempt to bring together various methodologies that will be vital for rising to this challenge in the future. Retinoid molecular biology has few methods of its own, but is reliant on standard molecular biology methods applied to this particular research area.