Poster abstracts
Poster number 39 submitted by Ila Marathe
Dissecting structural and functional cooperation in RNase P, a multi-subunit catalytic ribonucleoprotein
Ila Marathe (Department of Chemistry and Biochemistry), Lien Lai (Department of Chemistry and Biochemistry), Akiko Tanimoto (Department of Chemistry and Biochemistry), Yi Luo (Department of Physics), Vicki Wysocki (Department of Chemistry and Biochemistry), Michael Poirier (Department of Physics)
Abstract:
RNase P is an essential ribozyme that catalyzes Mg2+-aided maturation of tRNAs in all life forms. An RNase P RNA (RPR) and five RNase P proteins (RPPs) make up archaeal RNase P. In addition to serving as a model to uncover the cooperation between a catalytic RNA and multiple protein subunits, archaeal RNase P is an excellent proxy for the intractable and homologous eukaryotic cousin whose dysregulation leads to disease. Towards our goal of understanding how proteins modulate RNA catalysis, we focus here on archaeal L7Ae, a ribosomal protein that also acts as an RPP. L7Ae facilitates axial bending of RNAs by binding kink-turns, a widespread structural motif implicated in various aspects of RNA function. To test the hypothesis that L7Ae might aid in recruiting other RPPs to the RPR at physiological [Mg2+], we seek to uncover its roles in assembly of and catalysis by archaeal RNase P. By employing native mass spectrometry, single-molecule fluorescence, and activity assays, we expect to gain insights into: (i) stoichiometry of L7Ae, (ii) influence of L7Ae on the RNase P assembly landscape, and (iii) the ability of L7Ae to modulate the Mg2+ dependence of RNase P activity. Our results support the use of these methods to map the hierarchy and cooperation among RPPs in assembly and function of archaeal RNase P, and more broadly help elucidate the basis of human diseases where RNA-protein cooperation is defective.
Keywords: RNase P, RNA-protein cooperation, L7Ae