NEWS AND VIEWS A new model for circadian clock research?

From a closer and purer league betweenythe experimental and the rationalymuch may be hoped. (Bacon, 1620) Although Francis Bacon proposed the benefits of interdisci-plinary science in 1620, only recently have molecular biologists and mathematicians talked with any frequency. Although no modern biologist would deny the validity of computational approaches in biology—just look at the burgeoning field of Genomics—how useful mathematical modeling will be to biologists remains debated (Lawrence, 2004; Tyson, 2004). An answer may be here with a study in this issue of MSB by Locke et al (2005), which highlights the advantages of being able to work effectively with models and molecules. The study by Locke et al (2005) focuses on circadian rhythms, daily rhythms of behavior and physiology found in most organisms. These rhythms range from human sleep/ wake cycles to leaf movements in plants. The cyclical nature and the precision of these internally driven rhythms has intrigued mathematicians and biologists alike. Yet despite working on the same questions for decades, most circadian molecular biologists have not embraced mathematical model-ing. The following dialogue highlights similarities and differ-ences in the views of a biologist (B) and a mathematician (M): B: I don’t understand how ‘Math-Biology ’ will help my research—mathematical models seem more descriptive than predictive. M: Well, I have an excellent paper for you to read in which the authors move freely between computer simulations and experiments. Locke et al (2005) used experimental data to build a model, and then tested whether this model could predict other experimental data not initially included. Their initial model had only three genes in the network and did not match the in vivo data—so Locke et al added hypothetical components to make the model more accurate. Their simula-tions worked so well that they were able to return to experiments and identify a strong candidate for one of the hypothetical components. B: That does sound useful. What were they modeling