The projects in the Toorlab 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. For example, ~50% of the human genome consists of spliceosomal introns and non-LTR retroelements. Both of these are considered to have evolved from a class of introns which originated in bacteria billions of years ago called the group II introns. Group II introns share many structural and/or biochemical features with spliceosomal introns and non-LTR retroelements. Previously, I worked on determining the first crystal structure of a group II intron. This revealed the active site of this ribozyme to contain two catalytic metal ions coordinated by a conserved RNA structural motif called domain V. Since the group II and spliceosomal introns both share this RNA structure, spliceosomal introns should also have the same active site arrangement.