Oxford University Press (2001) 328 pages. ISBN 0-19-850820-4£29.95

Ernst Helmreich of the University of Würzburg begins The Biochemistry of Cell Signalling with Goethe's words`Everything worthwhile has already been thought. One can only try to think it over again.' Wise words indeed, but in view of the subject he might more aptly, albeit less patriotically, have quoted Poincaré's dictum `Science is built of facts,as a house is built of stones; but an accumulation of facts is no more a science than a heap of stones is a house.' Anyone whose research or teaching touches on intracellular signalling will be well aware of the vast number of bits now identified as pieces of that jigsaw and of the difficulty of even contemplating how a cell makes sense of it all. As a student once querulously remarked to me, `There's just too many proteins'.

With this in mind, it is perhaps not a bad idea to start an overview by saying what you're going to leave out, and this Helmreich does by presenting`fundamental aspects of cellular regulation' and omitting some `important aspects of cellular regulation'. That's fine in view, as the author points out, of the excellent textbooks on cellular and molecular biology available,and in the main it would be churlish to argue with the general content of this book: ligands, receptor tyrosine kinases, G-protein-coupled receptors, control of signalling pathways leading to modulation of transcription and, finally,the cell cycle and how loss of regulatory control may lead to cancer. Nevertheless, it seems somewhat perverse to omit any discussion of voltage-and ligand-gated ion channels whilst including a substantial chapter on regulation of the immune response. The latter is a useful immunology primer but, as the author comments, the essential features of the immune response`resemble receptormediated signalling by cytokines' and occur `through familiar structural motifs', and so a more abbreviated summary leaving space for discussion of ion channels might have been more appropriate. Furthermore,the immunology chapter rather impedes the flow from the cell cycle and apoptosis to transformation.

When it comes to the text there is certainly no arguing that it squeezes in an awful lot of facts, although the syntax might have the aforementioned Johann Wolfgang contemplating a bit of celestial rotational motion. The style throughout is a mixture of the brutal staccato (“TGFα is a growth factor. Its processing is of interest.”) and extended sentences with sprinklings of punctuation so eccentric their sole function is to ensure that you have to read the passage twice to get the message. Even after re-punctuating, there are places where the story remains either unclear or plain confusing, most notably in the cell cycle section, and there are a number of factual errors. For example, the members of the epidermal growth factor receptor family are not truncated versions of the EGFR - although loss of the extracellular domain of the latter has been observed in a number of tumours. The later sections on oncogenes and tumour suppressor genes are the weakest of the book. Examples receive rather fragmentary treatment and are somewhat arbitrarily selected. The error frequency creeps up - for example,the misleading title to Table 15.2, `Human cancers originating from retroviral infection', amplification of c-myc [sic], rather than NMYC, described as associated with neuroblastomas, all tumour suppressor genes said to encode transcriptional regulators, etc. The errors include an incorrect spelling of Boveri, which inevitably suggests that the author is on less than familiar ground in this field.

Despite these defects this book has considerable merit. There is no arguing that most key points are included, nor should the blemishes divert attention from its principal virtue - the schematic figures. These are only grayscale line drawings, many adapted from other sources, but almost without exception they are excellent. Even on well-worked ground - for example, transcriptional control - the `cartoons' are among the best and most informative I have seen. There are one or two exceptions, notably a figure representing DNA replication occurring in metaphase, but in the main they are outstandingly clear teaching aids. The schematics are supplemented by a set of colour plates of structures,used to illustrate aspects of protein interactions, and these are generally informative and not overemphasised.

Therefore, as with most newly completed structures, the builders have left a few piles of unincorporated stones lying around, there are one or two features you can't believe were in the original plans and there's the odd booby trap for the unwary. Even so, The Biochemistry of Cell Signalling takes up a previously vacant place in the range of biomedical textbooks with some distinction. The book is well worth having for the figures alone and, notwithstanding the above reservations, the text is jam packed with(mainly accurate) facts - though it may have you reaching for the phone occasionally to demand that the rough bits are tidied up.