After toiling in the lab over our constructs, we were able to examine all the conditions we desired. Moreover, our results closely followed our predictions. Across the board, the recruited effectors drastically decreased the mating output of the pathway (as measure by GFP fluorescence). These same effector proteins, when unable to bind to the scaffold, had significantly weaker effects. Additionally, our results showed that the irreversible negative efectors (YopJ and OspF) showed stronger repressive potency.
Our final step in this project was to build in feedback to the circuit. The previous experiments were performed with constitutive expression. In order to build a negative feedback loop, we placed the expression of the negative effectors under the control of a mating-induced promoter. As such, activation of the mating pathway will induce expression of an effector that will then proceed to shut the off the pathway. This will create behavior of dynamic adaptation after continuous stimulation with the pheromone (alpha-factor). The results confirmed this behavior—after 40 minutes of pathway activation, the expression of GFP comes to a halt.