Abstract 1721 Key Interactions of the Yeast Splicing Protein Dib1 Necessary for Spliceosomal Function

Pre-messenger RNA splicing involves the excision of non-coding RNA and the ligation of coding RNA to produce mature mRNA. This process is facilitated by the spliceosome, a multi-megadalton ribonucleoprotein complex. In Saccharomyces cerevisiae, Dib1, a 143 amino acid protein, resides at the catalytic core of the spliceosome and departs in the transition from the pre-catalytic spliceosome to the catalytically active spliceosome. Dib1's departure is crucial for spliceosomal activation. While the mechanism of Dib1's departure is uncharacterized, we propose that the flexible carboxy-tail of Dib1 plays a role in Dib1's association with the splicing machinery.