Characterizing the Multiple Binding Interactions of Air1 and Air2 from S. cerevisiae
Air1 and Air2 are highly homologous Eukaryotic proteins (45% sequence identity) that function in multiple nuclear RNA regulatory pathways, including RNA surveillance. The Air proteins are characterized as essential components of the multi-protein TRAMP complex (Trf4- Air2- Mtr4- Polyadenylation complex), which functions in nuclear RNA quality control by identifying RNA substrates and targeting them for degradation by the nuclear exosome. Within the TRAMP complex, Air1/2 mediate protein-protein interactions with both Mtr4 and Trf4. Furthermore, Air1/2 provides an essential RNA binding platform for the complex. Despite the significant role of Air1/2 in TRAMP, the mechanistic details of the critical protein-protein and protein-RNA interactions are poorly understood. Specific questions addressed in this study include: What is the binding interface of Air1/2 with the helicase Mtr4, and how do the Air proteins recognize various RNA substrates? Pull-down experiments using Air1/2 and Mtr4 truncation mutants are being used to identify the minimal binding interface between Air1/2 and Mtr4. A fluorescence based assay has also been developed to monitor Air1/2 interactions with various RNA species. Crystallization trials of viable complexes are ongoing.
Bakelar, Jeremy, "Characterizing the Multiple Binding Interactions of Air1 and Air2 from S. cerevisiae" (2014). Graduate Research Symposium. Paper 4.