Figure 6. Catalytic functions of condensates mediate the activation of a synthetic signaling circuit.

A, A reporter circuit was built using DmpR, a phenol activated transcription activator as a sensor, to drive the expression of EGFP, which serves a reporter protein for the cellular signaling. A condensate circuit was built to generate the cellular signaling event, which is mediated by condensates-mediated pNPP degradation to produce phenol. The coupling of these two circuits can be used to detect whether condensates have the capability to drive cellular signaling through degradation of pNPP from the culture medium.

B, The designed gene circuit follows a binary logic gate cascade with the formation of condensates and the existence of pNPP as the inputs to generate pNP, which activates DMPR to drive the expression of EGFP protein as the output.

C, Evaluation of the capability of condensates to mediate intracellular signaling with two circuits transformed into the BL21 (DE3) cells. The fluorescence signal was normalized to the cellular density. N = 6 independent experiment. Bar graph shows the mean ± SD.

D, Evaluation of the capability of condensates to mediate intercellular signaling with the condensate circuit transformed into the E. Coli. BL21 (DE3) cells and the reporter circuit transformed into the E. Coli. DH5α cells. The fluorescence signal was normalized to the cellular density. N = 6 independent experiment. Bar graph shows the mean ± SD.