Michaëlle N. Mayalu

Abstract Synthetic biology enables the precise control of bacterial population dynamics through engineered genetic circuits, paving the way for innovative therapeutic and biosensing applications. Here, we present genetic circuit design that leverages AHL (acyl-homoserine lactone)-based quorum sensing and a transcriptional cascade regulated by an external inducer to drive synchronized proliferation and lysis events.

Highlights • Engineered mammalian cells send and perceive signals using the plant hormone auxin • Auxin signaling allows quorum sensing by engineered cells • Coupling auxin sensing to survival allows cells to control their own population size • A paradoxical design makes population control robust to cheater mutations Summary In multicellular organisms, cells actively sense and control their own population density.