The projects in his lab focus on the structure and function of non-coding regions of prokaryotic and eukaryotic genomes. Two genetic elements particularly abundant in these organisms are introns and retroelements, which comprise ~50% of the human genome. Previously, he worked to determine the first crystal structure of a group II intron. Group II introns are thought to be the ancestors of all the introns and retroelements found in higher organisms. Due to this evolutionary relationship, the crystal structure revealed the catalytic mechanism behind RNA splicing in eukaryotes.