RNA molecules are the most functionally diverse biopolymers on Earth, but we know little about their structures and behaviors. In the Pyle lab, we explore the structural complexity of RNA molecules and the proteins that bind them, focusing on three major areas: A. The tertiary structures and folding pathways of long noncoding RNAs, such as the self-splicing group II introns. B. The molecular mechanism of RNA helicase proteins and RNA-triggered mechanical devices, such as the RIG-I innate immune sensor. C. Development of new experimental and computational tools for studying RNA structure. Our investigations have carried us into the fields of virology, innate immunity, RNA processing and molecular evolution. But our findings are relevant to all of the many tasks of RNA in the cell.