Synthetic memory in eukaryotes?

Scientists have engineered a DNA-based device that enables eukaryotic cells to "remember" past exposure to a specific stimulus, according to a new report in Genes and Development. The researchers used a mathematical model to design a genetic switch, triggered by the small sugar molecule, galactose, that maintains steady production of proteins even after the galactose is removed. Similar past efforts in eukaryotes have instead relied on trial and error. The study shows the possibility of building not just fully functional but also completely predictable synthetic components inside the nuclei of single cells, the authors say. "It's a really nice study. It will help set the stage for additional rational approaches in eukaryotes," James Collins of Boston University, who was not involved in the work, told The Scientist. He explained that other researchers have used models to describe similar systems in eukaryotes but only after they actually built their...