All cellular functions, activities, and communications are mediated by protein interactions. Despite their crucial importance, we know relatively little about many of these interactions due in large part to experimental limitations of structural biology. The central theme of my lab revolves around the determination of the structure and elucidation of the molecular mechanisms of highly dynamic and transient protein interactions. Our current efforts are focused on understanding the assembly and functional interactions of the low-complexity domains of RNA-binding proteins involved in cancer and neurodegenerative processes. In particular we are interested in the oncogenic fusion protein EWS-Fli1 and the structural implications of its role as the sole driver of Ewing’s sarcoma. These types of proteins are challenging targets for biophysical characterization due to their extreme structural heterogeneity and propensity to aggregate.