Programming Artificial Cells as Bidirectional Genetic Thermometers

High Resolution Image Download MS PowerPoint Slide Cell-free protein synthesis (CFPS) systems offer a powerful platform for engineering synthetic gene circuits with rapid prototyping and modular control. Using this technique, artificial cells have been produced for a range of biomedical applications, such as biosensing, drug delivery, and tissue engineering. However, associated regulatory strategies rely predominantly on chemical induction, lacking the spatiotemporal precision required for clinical translation. Here, we engineer a bidirectional genetic thermometer using the TlpA transcriptional regulator, achieving bidirectional thermal regulation in both CFPS and artificial cells. Counter to its canonical role as a high-temperature regulator in living systems, TlpA exhibited temperature-dependent activation and repression in CFPS, enabling programmable gene expression across discrete thermal thresholds. Our bidirectional thermometers were integrated into alginate microbeads, creating functional thermal microsensors on a path toward smart thermal materials. This work establishes a bidirectional temperature control system for artificial cells and offers insights into the integration of genetic circuits with biomaterial engineering.