Paths to life and to death

Charles Darwin's book The Power of Movement in Plants (1880) postulated the presence of an "influence" that caused the stem of a plant to bend towards light. The phototropic substance was the hormone auxin discovered by Frits Went. From its origins in Victorian greenhouses, the field of cell signalling has grown exponentially and today touches on almost every area of biology and biomedicine.

John Hancock's Cell Signalling makes a vast and, at times, bewildering subject accessible to non-specialists. The opening chapter outlines the basic principles. A signal arrives at the cell and is recognised by a receptor, which sets in motion an amplifying cascade of events that ultimately leads to a response. The complexity lies in the fact that cells encounter not one but many coincident signals. Mechanisms are called for, at once, to compartmentalise and integrate different pathways that may use common components.

Seven chapters are devoted to the components of signalling pathways: hormones, cytokines, growth factors, neurotransmitters and pheromones; receptors linked to ion-channels, G-proteins and tyrosine kinases; and a host of effectors (kinases, phosphatases, cyclases) and mobile messengers (calcium, cyclic nucleotides, inositol phosphates, nitric oxide).

Having assembled the cast, Hancock selects insulin signalling and visual transduction to illustrate how the various players may act in concert. I was disappointed that the book does not include more such signalling pathways that are integral to the life and work of cells and indeed - as the penultimate chapter on apoptosis demonstrates - to their decision to die.

This new edition of Cell Signalling , updated to include recent advances, is livelier than its predecessor. Students will like this work, which is aimed primarily at second and final-year undergraduates, for its easy-to-read style, bullet-point summaries and boxes containing definitions and historical or biographical asides. The figures, enriched by a dash of colour, are available to instructors on the companion website.

Pauline Phelan is lecturer in cell biology, University of Kent at Canterbury.