Research in the Williamson lab is in the area of RNA-protein interactions using a broadly based biophysical approach. Areas of focus include regulatory complexes of HIV Tat and Rev interacting with the TAR and RRE RNA structures, respectively. Williamson determined the structure of the HIV TAR-arginine complex and the Rev-RRE complex using NMR spectroscopy, which were among the first viral RNA structures to be determined. In addition, Williamson studies the mechanism of prokaryotic ribosome assembly, and RNA-protein complexes involved in regulation of C. elegans germline development.