Schematic. Credit: Nature (2025). DOI: 10.1038/s41586-025-09310-6 To our immune system, naked RNA is a sign of a viral or bacterial invasion and must be attacked. But our own cells also have RNA. To ward off trouble, our cells clothe their RNA in sugars, Vijay Rathinam and colleagues at the UConn School of Medicine and Ryan Flynn at Boston Children's Hospital report in Nature. Ribonucleic acid (RNA) is a family of large biological molecules fundamental to all forms of life, including viruses, ba...