Cell, Vol. 18, 229-231,
Advances in Cyclic Nucleotide Research, 10, Current Methodology. G. Brooker, P. Greengard and G. A. Robison, eds. New York: Raven Press. 259 pp. $24.00.
Research on cyclic nucleotides has expanded to such an extent that it now touches upon a large variety of biological topics ranging from gene expression in bacteria to growth and differentiation in higher organisms, and the number of investigators engaged in cyclic nucleotide research has increased accordingly. It is therefore essential that a detailed description and evaluation of methodology for cyclic nucleotide research be available. Volume 10 in the series of Advances in Cyclic Nucleotide Research fulfills this need. This timely book is organized and written in such a manner that both beginners and experienced investigators in cyclic nucleotide research will find it of value and interest. Principles of assays and detailed descriptions of assay procedures are provided for the methods of analysis. Chapters are included which deal with the quantitation of cyclic AMP and cyclic GMP by radioimmunoassay, and the assay systems %or adenylate cyclase, guanylate cyclase and cyclic nucleotide phosphodiesterase. Cyclic nucleotide-dependent protein kinase assay procedures are described and an additional chapter detailing methods currently in use to evaluate endogenous phosphorylation in cell-free and intact cell preparations is presented. Additional methodology is provided for immunocytochemical localization of cyclic nucleotides and protein kinase and also for isolation of cyclic nucleotide receptor protein by affinity chromatography. A recent exciting advance related to cyclic nucleotide research is the discovery and evaluation of the Ca++ -dependent modulator protein. One chapter is devoted to the preparation and assay of this protein. It is well known that enzymes in cyclic nucleotide metabolism are activated by divalent cations and that substrate and product nucleotides act as chelating agents. A description of chelation theory and tabulations of chelation properties of nucleotides and the commonly used chelating agents, EDTA and EGTA, are presented. Tables in this chapter are useful for experiments in which it is essential to know the concentrations of bound and free cations. An informative chapter describing recent techniques for enzymatic preparation of labeled nucleotides with high specific activity is included as well. Those investigators on a limited research budget will find this chapter quite useful.
This recent volume in this popular for those studying cyclic nucleotide function.
series is a must metabolism and
George S. Johnson Laboratory of Molecular Biology National Cancer Institute Bethesda, Maryland 20205
Inhibitors of Protein Biosynthesis. Molecular Biology, Biochemistry and Biophysics, 30. By D. Vazquez. Berlin, Heidelberg, New York: Springer-Verlag. 312 pp. $32.50.
It has been said that if we could lay hands on specific inhibitors of all the metabolic processes we know, the task of elucidating those we do not understand would be that much easier. Pie in the sky, perhaps, but there can be few readers of this journal who have failed to use antibiotics or related substances as tools to inhibit some aspect of macromolecular biosynthesis at one time or another: mitomycin or FUDR to block DNA synthesis; actinomycin to inhibit gene expression by interfering with the template function of DNA; rifampicin to block transcription in procaryotic cells, or (Yamanitin to prevent transcription by eucaryotic RNA polymerase II; chloramphenicol or cycloheximide to inhibit translation of mRNA by procaryotic or eucaryotic cytoplasmic ribosomes, respectively. The list is long, and still longer if one includes such multipurpose agents as the classic intercalative DNA binder ethidium bromide (originally developed as an effective trypanocidal drug for veterinary use, remember, although now consumed on the kilogram scale in laboratories around the world for anything from isolating circular DNA to whacking mitochondria or staining gels). Specificity (or better, biochemical selectivity) is the crucial element in this story-not so much selective toxicity toward different cell types as originally envisaged by Ehrlich, although that is not without relevance to many an area of current research (to say nothing of human need as the strategy of chemotherapy moves into its fifth decade), but the capacity to discriminate effectively between biochemical processes. If necessary, conditions must be judiciously chosen so that the investigator can pinpoint the lesion he has introduced into the biological system in order to interpret
its effects. In such a situation the technician is only as good as his tools will allow; hence the need for a thorough understanding of the mechanism(s) of drug action if an approach of this sort is to be of any value at all. Here Vazquez comes to our aid on the subject of protein synthesis inhibitors, as did the Kerstens in a preceding volume in this series (78) dealing with inhibitors of nucleic acid synthesis. The new book is a veritable mine of information and a model of rectitude. Its comprehensive coverage of the topic in so small a space (201 pages of text, each photographically reproduced from a double-spaced typescript page) is impressive, and the thoroughness with which the author has covered the literature can be gauged from the fact that it took another 104 pages to print his reference list. One might be forgiven for wondering how many references escaped inclusion. There is an index, but it is rather rudimentary in that it is virtually limited to listing the names of the inhibitors dealt with (which came to a staggering 420 compounds by my quick count). Vazquez treats his subject matter in strictly logical order: after a brief introductory section which provides an overview of the scope of the subject, including some carefully prepared summary tables and figures, he proceeds to deal in turn with inhibitors of initiation, elongation and termination of the polypeptide chain, disposing of the multifarious compounds which do not act at the level of the ribosome in the first table of the introductory chapter. He concludes with three very short chapters on miscellaneous inhibitors of translation, GTP analogs and a very guarded “reconsideration” of selectivity and specificity. The logic of the layout is undeniably impeccable but it inevitably leads to quite disproportionate division into chapters: it takes about 36 pages to deal with initiation and a mere four to cover termination, while the bulk of the text consists of the chapter on inhibitors of elongation (133 pages). The author has interpreted his brief to compile a treatise on “inhibitors” as widely as possible: included are the antibiotics; the synthetic chemotherapeutic drugs; toxins, experimental tools and substrates ionophores, amphetamines and cyclic AMP receive mention. Even such harmless (?) species as ethanol, Cl- ions and glycogen polymers have not escaped his eagle eye. Nor, for that matter, has temperature shiftdown (p. 47). Throughout the treatment is meticulous and scrupulously fair. Where issues are evidently controversial they are sensitively and carefully documented, as in the discussion of hemin-controlled repressor, interferon and related matters on pp. 22-27. One message which comes across clearly is the difficulty of categorizing inhibitors in terms of primary effects on initiation, elongation or termination: we have long been familiar with the controversy over whether
streptomycin and other aminoglycoside antibiotics should be thought of primarily as inhibitors of initiation, but readers may be surprised to find that evidence of selective effects on all three phases of polypeptide chain synthesis has been reported for cycloheximide (pp. 155-l 58). Here and there an occasional misspelling or unusual usage adds a little color to the text (inmediate, p. 2; a-amino-b-clorobutyrate, p. 4; micotoxin, p. 193) but on the whole the language is clear and straightforward; only rarely is a misprint likely to amuse (alphalpha, p. 33) or mislead (diphosphorylated for dephosphorylated, p. 24, line 8 up). However, the usefulness of the book to students will be limited by the need to have a fairly advanced and up-to-date grasp of the basic mechanisms of protein synthesis and the assay systems used to study the various complex stages of initiation, elongation and termination reactions. This will not daunt the research worker, who can hardly fail to learn much from Vazquez’s compendious work. Furthermore, the intricacies of the assemblage of three RNAs plus fifty-odd proteins (not to mention an array of “soluble” accessory factors) which constitute the ribosomal protein-synthesizing system still present problems of sufficient complexity that those who have chosen this field as the focus of their interests need not worry about making a change for at least a few more years. Vazquez’s book should give them plenty to get their teeth into. Michael J. Waring Department of Pharmacology University of Cambridge Medical Cambridge CB2 2QD, England
Methods in Membrane Biology, 10. E. D. Korn, ed. New York and London: Plenum Press. 227 pp. $29.50.
There is a need for detailed and critical descriptions of the methodology used in membrane research in physiology, biochemistry and biophysics. Particularly in areas where the special problems of membrane systems necessitate the development of new procedures, it is invaluable for students and investigators changing areas to have access to a compilation of workable methods and a discussion of their limitations. For the most part, the chapters in the series Methods in Membrane Biology (started in 1974) edited by Korn, fill this need admirably. They are not