  The structure of a stochastic nonlinear gene regulatory network is uncovered
by studying its response to input signal generators. Four applications are
studied in detail: a nonlinear connection of two linear systems, the design of
a logic pulse, a molecular amplifier and the interference of three signal
generators in E2F1 regulatory element. The gene interactions are presented
using molecular diagrams that have a precise mathematical structure and retain
the biological meaning of the processes.
