Communication and Cross‐Regulation between Chemically Fueled Sender and Receiver Reaction Networks**

Nature connects multiple fuel-driven chemical/enzymatic reaction networks (CRNs/ERNs) via cross-regulation to hierarchically control biofunctions for a tailored adaption in complex sensory landscapes. Herein, we introduce facile example of communication and among two DNA-based ERNs regulated by concatenated RNA transcription regulator. ERN1 (“sender”) is designed the promoter formation T7 polymerase, which activates transcription. The produced can deactivate or activate DNA ERN2 (“receiver”) toehold-mediated strand displacement, leading between ERNs. from repress promote state ERN2; turn feedbacks regulate lifetime ERN1. Furthermore, incorporation RNase H allows degradation enables autonomous recovery ERN2. We believe that concatenation CRNs/ERNs provides basis design more elaborate regulatory mechanisms systems chemistry synthetic biology.