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bioRxiv · 10.1101/2025.05.13.653855

Integrating Recombinase-Based Feedback and Feedforward Control for Optimal Resource Decoupling

Zhang, R.·Tian, X.-J.
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Abstract

Resource competition disrupts circuit modularity by introducing unintended coupling between otherwise independent gene modules, thereby compromising genetic circuit function. While various control strategies have been explored, their complexity or limited efficacy has hindered broader application. Here, we present the Re-NF-FF-Controller, a recombinase-based strategy that integrates negative feedback and feedforward regulation via promoter flipping to mitigate resource competition. Computational modeling and experimental validation demonstrate that Re-NF-FF-Controller effectively reduces resource coupling, ensuring robust gene expression and modularity. Moreover, its tunability allows for performance optimization through straightforward adjustments of recombinase enzyme levels. This strategy offers a versatile and easily implementable solution for designing reliable synthetic biological systems. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=78 SRC="FIGDIR/small/653855v1_ufig1.gif" ALT="Figure 1"> View larger version (15K): org.highwire.dtl.DTLVardef@6b960forg.highwire.dtl.DTLVardef@148bc3borg.highwire.dtl.DTLVardef@3df13borg.highwire.dtl.DTLVardef@a865f2_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Zhang, R., Tian, X.-J.. 2025-05-14. Integrating Recombinase-Based Feedback and Feedforward Control for Optimal Resource Decoupling. https://doi.org/10.1101/2025.05.13.653855

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