Figure 4.

From genes to logic circuits. (A) Visualization of the abstraction levels encountered in GDA. The gene circuit at the bottom realizes the behavior within the cell and is the circuit our model is applied to. It relies on protein concentrations as signal carriers. Defined on top, the genetic logic circuit provides a convenient interpretation in terms of gates, familiar to engineering disciplines and the basis for GDA. The Boolean logic circuit shadows all implementational details and presents the function to realize. (B) Overview on the energy demands of a genetic NOR gate following the implementation of ref (40). The gate consists of the genes a, b, and c, with the preceding and succeeding gates greyed out. ϵ_tx denotes the energy dissipation rate of the RNA dynamics, ϵ_tl of the protein dynamics, and ϵ_p is the energy dissipation rate of the promoter.