Abstract

Biological networks are extremely complex objects. Still representation of them remains to be very simple. Here hypothesis representing all regulatory cellular processes as cycles connected to each other is provided. Cycles were introduced as minimal parts of network containing negative feedback loop. All cycles were interconnected between each other by common members of network; it can be gene, protein or metabolite. Gene networks, metabolic networks and signaling cascades were represented as cycles with different characteristic period of oscillations. Dynamical connectivity takes place according to the period of oscillations. The period of high frequency oscillation must be “drawn” into the period of low frequency oscillation at least to avoid destructive interference of oscillations and moreover to maintain low frequency process that is supposed to be circadian rhythm and presumably cell cycle. So, corresponding multi-level model of regulatory networks as a composition of cycles which function as complex modular molecular clocks represented. This model shed light on biological networks at molecular level organizations and dynamics.

Key words: Gene network, metabolic network, signaling networks, negative feedback loop, oscillations, molecular clock, circadian rhythm.