Figure 4

Average number of TetR2 molecules for different number of administered Tc molecules. At the beginning, there is about 1 TetR2 molecule in the cell. At time equal to 5 hours, a pulse of various Tc amounts is administered to each cell and thus gene expression is induced. Then, the amount of the free (unbound) TetR2 decreases, because these proteins are occupied by Tc, and thereafter increases upon expression of tetR. Increasing amount of administered Tc results in higher decrease in TetR2 amount and longer required time for going back to steady state.