cell function; 4. Quantitative aspects of protein synthesis in early embryos: the role 

 of maternal components; 5. Transcription in early embryos; 6. RNA sequence complexity 

 and structural gene transcription in early embryos; 7. Localization of morphogenetic 

 determinants in egg cytoplasm; 8. Lampbrush chromosomes and the synthesis of hetero- 

 geneous nuclear and messenger RNA's during oogenesis 



An indication of the enormous growth of the area covered by this book is the length 

 of the bibliography, which has almost doubled since the first edition even though part of 

 the original references have been deleted. The contents of the book have been consider- 

 ably rearranged and the book is in fact almost a new one. We must be grateful to the 

 author for undertaking this arduous task with such excellent results and without unduly 

 increasing the size. That the treatment is basically organised around his personal views 

 and interpretations is understandable and increases rather than decreases the book's value. 



As in the first edition, the basic tenet is that regulation at the transcriptional level is 

 the fundamental process underlying differentiation and development. This, and the em- 

 phasis on early stages, is probably the reason why a class of problems which are considered 

 fundamental by many embryologists, i.e. induction, determination and competence, 

 receive little or no attention as subjects in their own right. One hopes that these pro- 

 blems, though elusive at present, will also capture the attention of molecular embryo- 

 logists in the years to come. 



Apart from numerous extensions of the original material, the major new features are 

 ch.4 and the first section of ch.6, which deals with nucleic acid sequence complexity and 

 the kinetics of renaturation and hybridisation. 



The book is attractively produced and illustrated. The 48-page bibliography is remark- 

 ably up to date. (An oddity is that Crawford and Wilde's 1973 experiments with pacta- 

 mycin in Fundulus are not included.) The absence of an author index is to be regretted; it 

 would have been easy to use the bibliography for that purpose. 



Monographs 



95. 



N.MACLEAN. 1976. CONTROL OF GENE EXPRESSION 



Academic Press, London, etc. XII, 348 pp., 21 figs., 6 tabs., author and subject index- 

 es. £ 7.80, $ 19.25 



Contents: 1. The control of gene expression and its levels of action; 2. Gene expression 

 in prokaryotes; 3. Experimental systems of differential gene function in eukaryotes - 

 systems involving one type of protein; 4. Experimental systems of differential gene 

 functions in eukaryotes - systems of limited complexity; 5. Experimental system of 

 differential gene functions in eukaryotes - systems not well understood in molecular 

 terms; 6. RNA involvement in gene expression; 7. General concepts of gene regulation 



The level of treatment in this well-written book is between that of an introduction and 

 that of a specialised monograph. For the student making up his mind on what research 

 to embark on it is a stimulating guide. The main function it may perform for the specialist 

 is to make him more aware of the advances in and the potential of systems other than that 

 on which he happens to be working. 



The main substance of the book is to be found in chapters 3-5. In ch.3 "system" means 

 a particular type of protein; eight such proteins are discussed, ranging from immunoglo- 

 bulins to vertebrate egg proteins and including two insect proteins. In chs. 4 and 5 

 "system" usually means a tissue, organ or organism, occasionally an approach or a class of 

 proteins. Many phyla, both plant and animal, are represented. 



The bibHography, though selective, covers 34 pages and is up to date until 1974. The 

 book is attractively produced and illustrated. 



230 



