Small molecules set up security system to defend the genome - Heng-Chi Lee, Ph.D.

Thousands of short RNA molecules with diverse genetic sequences serve as security guards to identify and silence attempts to invade the genome, such as DNA inserted by viruses or parasitic elements known as transposons.

“Nearly every animal has these small RNAs, and they use them as a guide to look for target sequences and silence them,” said Heng-Chi Lee, PhD, assistant professor of molecular genetics and cell biology at UChicago and senior author of the new study. “Until now though, it was rather mysterious what their function was, and why there are so many with such diverse genetic sequences.”