Systems analysis in cell biology: from the phenomenological description towards a computer model of the intracellular signal transduction network.

In this paper we introduce a systematic approach for the modelling of complex biological systems which is especially useful for the analysis of signal transduction mechanisms in cell biology. It is shown that systems analysis in form of top-down levelled dataflow diagrams provides a powerful tool for the mathematical modelling of the system in terms of a stochastic formulation. Due to the exact formulation, the consistency of the model with the experimental results can be tested by means of a computer simulation. The method termed Structured Biological Modelling (SBM) is illustrated by modelling some aspects of the second messenger network which regulates cell proliferation. As an example for the straightforward development of a mathematical description a stochastic computer model for intracellular Ca2+ oscillations is presented.