Circular RNAs, like other noncoding RNAs, were thought to be nonfunctional, but recent evidence suggests otherwise. Circular RNAs may in fact act like sponges to ‘soak up,’ or bind, other molecules, including microRNAs and proteins, and new work supports this idea. They describe, for the first time, a circular RNA that fills a critical role in tissue repair after heart attack, thanks to its ability to soak up harmful molecules.
