Molecular biology

Abstract

Molecular Biology Robert Weaver, 3rd Ed., McGraw-Hill, New York, 2005, 894 pp., ISBN 0-072-84611-9, $138.13 Akif Uzman uzmana@uhd.edu*, * Department of Natural Sciences, University of Houston–Downtown, Houston, TX 77002. The explosion of biochemical information in the past 20 years has made it difficult to determine what content to cover in an upper division course in molecular biology. Lewin's Genes texts have increased in thickness steadily during this time such that it has become another one volume encyclopedia akin to the massive texts of Alberts et al. and Lodish et al. for cell biology. The first edition of Weaver's text Molecular Biology in 1999 represented a significant departure in pedagogic approach to the presentation of molecular biology, and to date there is no textbook like it. Molecular Biology is not a compendium of facts but an 894-page discourse on the experiments that reveal our current understanding of the biochemical mechanisms underlying the many processes of the central dogma of molecular biology. Molecular Biology is extraordinarily rich in experimental detail and so is an outstanding text with which to teach experimental analysis to seniors or first year graduate students. On the other hand, if one wishes to teach a survey course in molecular biology, then Genes VIII by Benjamin Lewin, Molecular Biology of the Gene Fifth Edition by James Watson et al., or Genomes 3 by Terry Brown is better. Malacinski's Essentials of Molecular Biology is also suitable for those offering a sophomore-level course focusing on prokaryotic molecular biology. Molecular Biology is divided into eight parts: Introduction, Methods of Molecular Biology, Transcription in Prokaryotes, Transcription in Eukaryotes, Posttranscriptional Events, Translation, Replication, Recombination and Transposition, and Genomes. The focus throughout the text is how specific experiments reveal specific knowledge. The canonical experiments of molecular biology of which everyone is familiar are here along with many, many others ranging from experiments demonstrating promoter clearance, order of RNA edition, identification of branched nucleotide formation during RNA splicing, editing in protein synthesis, and many others less familiar to most outside of molecular biology. Most of the chapters have at least nine experiments analyzed in detail, and a few chapters contain as many as 13 experiments. The experimental data presented come directly from the original published work and are not idealized data as one often finds in the more popular texts in molecular and cell biology. Supplementing the real data are diagrams that provide a clear conceptual framework from which to understand the experiments discussed. There is also a nice blend of structural biochemistry integrated into the discussion to illustrate the molecular details of several reactions in transcription, translation, RNA processing, and DNA replication. A surprising omission is that the topological analysis of DNA supercoiling is absent. Indeed, there are elegant experiments from Wang and Crick as well as Cozzarelli and his colleagues that are important to the canon of molecular biology but are absent in this book. While the chapters in the Methods of Molecular Biology (Chapters 4 and 5) present most of the key experimental tools of the trade, numerous other methods are also presented throughout the text. One of my favorite features of this text is that after the detailed table of contents is a two page index of over 90 molecular techniques presented in the book (!), most of them integrated into the discussion of material outside of Chapters 4 and 5. The single chapter in the Genomes section (Chapter 24, Genomics and Proteomics) is comparatively terse and lacks the depth of the rest of the book. Still, the experimental approach is evident here. What the content lacks is the conceptual background in bioinformatics to bring this material to the same level of sophistication as the rest of the text. This is an understandable omission to some extent since this material strays from the central purpose of the text, which is a sophisticated presentation of the mechanisms operating in the reactions of DNA replication and recombination, transcription, and RNA processing and translation. This purpose also reveals another absence in the text, a broader presentation of the role of differential gene expression in biology, the prominent reason molecular biology holds a strong interest for most biologists. Hence, if an instructor wants to delve into gene regulation, there is too little in Molecular Biology that really satisfies beyond the life history strategies of bacteriophage lambda. Promoter regions of several eukaryotic genes have been analyzed in spectacular detail such that the brief mention of the sea urchin endo16 gene is disappointing. While the author does not completely omit regulatory phenomena, little attention is paid to the significance of regulation in a larger context. For instance, the role of PHAS-I is discussed briefly in the context of the regulation of eukaryotic initiation factor-4E, but the importance of this regulation to the biochemistry of the cell is given scant attention such that students are left with an isolated regulatory mechanism with no integration into a larger biological context. What a future edition of Molecular Biology needs is a chapter devoted to transcriptional regulation with the same rigor and detail Professor Weaver brings to the mechanisms of the transcriptional apparatus discussed in Chapters 11, 12, and 13. Another weakness is the inattention paid to quantitative parameters of replication, transcription, and translation. Most of the discussion is focused on experiments revealing a qualitative description of these biochemical processes. Indeed, there is important quantitative work that reveals important regulatory features of transcription in pro- karyotic operons, eukaryotic RNA processing, and translation. The end of each chapter has an extensive list of review questions and references. The references include seminal research papers along with relatively recent reviews. The review questions walk the students through the experimental evidence and key ideas. Surprisingly, there are only 3–4 analytical questions at the end of most of the chapters. With three editions of this text produced across the last seven years, I am surprised that McGraw-Hill has not been able to entice someone to assemble a problems book to Molecular Biology or develop more analytical questions for this text. A CD-ROM is available that contains PowerPoint images of the diagrams but not the experimental data; for that you need to go to the instructor resources website where you can download PowerPoint presentations for each chapter that contain most of the experimental data present in the book. Molecular Biology can be a challenging book from which to teach; the shear density of experimental discussions can overwhelm undergraduate students, and the writing style is often dry and turgid. Fortunately, Molecular Biology is remarkably free of obvious errors or confusions. For any instructor wishing to integrate analytical approaches to the presentation molecular biology, Weaver's Molecular Biology is an outstanding one-of-a-kind source of material for developing problem-based exercises or teaching a course in molecular biology that goes beyond the typical descriptive survey of the biochemistry of the central dogma.