Fig. 2: Synthetic DNA sponge enables tuning output gene expression by decoying receptors within circuits’ input sensing modules.
From: Synthetic protein-binding DNA sponge as a tool to tune gene expression and mitigate protein toxicity
a Schematic showing the design of two types of synthetic DNA sponges to decoy TetR in an aTc-responsive circuit: 1–320 repeats of TetR operator (tetO) or 1–40 repeats of Ptet2 promoter. b, c The aTc responsive circuit’s dose-responses with sponges containing different numbers of the tetO (b) or the Ptet2 repeats (c). d Induction fold between uninduced and 200 ng/mL aTc induced samples of the circuit with or without the tetO/Ptet2-based sponge regulation as characterized in (b, c). e Hill constant (KM) of the circuit’s fitted dose-responses from (b, c) against different repeat numbers of the tetO/Ptet2-containing sponge. KM value of sample with sponge containing 320 tetO repeats is not shown due to insufficient dose-response of the circuit. f Design of an AHL-responsive circuit with regulation by sponges containing 1–80 repeats of the LuxR binding site (LBS). g Dose-responses of the AHL-responsive circuit with sponges containing different numbers of LBS repeats. h Hill constant (KM) of the circuit’s fitted dose-responses from (g) against different repeat numbers of the LBS-containing sponge. For (b–d, g), values are mean ± s.d. (n = 3 biologically independent samples). For (e, h), values are mean ± s.e.m. (n = 3 biologically independent samples). Fluo., fluorescence. a.u., arbitrary units. Source data are provided as a Source Data file.
