Poster abstracts

Poster number 7 submitted by Jessica Spears

Widespread tRNA Editing in Trypanosomatids

Jessica Spears (Microbiology; The Ohio State University), Kirk Gaston (Microbiology; The Ohio State University), Mary Anne Rubio (Microbiology; The Ohio State University), Juan Alfonzo (Microbiology; The Ohio State University)

Abstract:
Although RNA editing is widespread in nature, cytidine (C) to Uridine (U) editing of tRNA has only been found in organelles (mitochondria and chloroplast). We show here that all three tRNAThr isoacceptors in Leishmania tarentolae and Trypanosoma brucei undergo C to U editing in the nucleus. This represents the only known tRNA C to U editing event that occurs outside of mitochondria or chloroplasts. The significance of this observation rests in the fact that when looking at editing levels, for each isoacceptor, aminoacylated tRNAs are edited to a higher extent than what is found in the total tRNA population. Also, in all cases, a higher percentage of the tRNA is edited in cytoplasmic as compared to nuclear RNA fractions. Taken together these observations imply that the edited species are not only functional in these organisms but while produced in the nucleus, they are preferentially exported to and aminoacylated in the cytoplasm. These findings also indicate that tRNA editing is more widespread than previously thought and it is not limited to eukaryotic organelles.

Keywords: tRNA, editing, kinetoplastid