Fig. 5.

Direct transcriptional regulation (DTR) vs indirect translational regulation (ITR) at equal resources. (a) Comparison of the maximal capacity as a function of C between indirect translational regulation (ITR, red curves) and direct transcriptional regulation (DTR, black curves) scenarios, for three values of total resource cost (total mRNA number), $ℳ$. Here, y_max = 10, F = 1. Compared to Fig. 2, ITR stops being beneficial over DTR at lower C. (b) Capacity difference between the ITR and DTR models as a function of C and $ℳ$. The thick red line marks the $(C,ℳ)$ values that lead to equal capacities; in the regime above the red line ITR, in spite of intermediary regulatory steps, is beneficial over DTR.