In the 30 years between the discovery of microRNAs and their recognition with the Nobel Prize in 2024, a great deal has been learned about how these molecules function in the cytoplasm of cells and their primary role in silencing genes. However, more recent findings suggest that microRNAs might have important functions in another location: the mitochondria, the amazing organelles in our cells that possess their own DNA and synthesize their own proteins. This seminar teaches us about new tools for studying microRNAs now allow for their functions to be more clearly understood, such as what roles they play in the mitochondria and how they might be contributing to diseases such as cancer. Our speaker, Dr. William (Billy) Mills is the principal investigator of the Mills Lab at Mount St. Mary’s University in Emmitsburg, MD where he studies the roles of microRNAs in differentiation, development, and disease.