A synthetic oscillator that switches between two cellular aging processes can boost the lifespan of yeast cells by more than 80 percent, according to a report in Science. The work highlights the potential of synthetic biology to enhance longevity. While advances in synthetic biology are enabling the design of gene networks that can confer specific biological functions, doing so with a trait as complex as longevity remains extremely challenging. Aiming to overcome this, University of California, San Diego scientists rewired a naturally occurring toggle switch that underlies fate decisions toward either nucleolar or mitochondrial decline during the aging of yeast cells to generate sustained oscillations between the two processes in individual cells. The oscillations, they show, delays the commitment of yeast cells to either of the aging processes, increasing life span up to 82 percent versus wild-type cells. "Our work represents a proof-of-concept, demonstrating the successful application of synthetic biology to reprogram the cellular aging process, and may lay the foundation for designing synthetic gene circuits to effectively promote longevity in more complex organisms," the researchers write.