Poster abstracts

Poster number 92 submitted by Allyson Morris

Investigating the effects of PUS5 deletion on mitochondrial encoded protein expression in Candida albicans and Saccharomyces cerevisiae

Allyson R. Morris (Department of Biology, Ball State University ), Douglas A. Bernstein (Department of Biology, Ball State University )

Abstract:
While RNA is made of only 4 bases, these bases can be modified in over 100 distinct ways. These modifications play critical roles modulating RNA function. Pseudouridine is the most common modified nucleoside, and is found in all kingdoms of life. However, the role of pseudouridylation in translation and RNA function is not well understood. Pseudouridylation is found at dozens of sites in Eukaryotic cytoplasmic rRNA and cytoplasmic ribosomes translate thousands of proteins. As such, it is challenging to study the effects individual sites of pseudouridylation have on translation. In contrast, in fungi, mitochondrial ribosomes translate only eight genes encoded by the mitochondrial genome and mitochondrial rRNA contains only one highly conserved pseudouridine which is made by the pseudouridine synthase Pus5. We find Saccharomyces cerevisiae pus5Δ deletion is more sensitive to drugs that inhibit oxidative phosphorylation such as oligomycin, suggesting they have a defect in mitochondrial function. We will investigate the roles of Pus5 mediated pseudouridylation on mitochondrial protein expression. We will use mass spectrometry to determine if mitochondrial rRNA pseudouridylation is required for wild type mitochondrial gene translation. Investigation of this highly conserved RNA modification will lead to a better understanding of how defects in pseudouridylation lead to human disease and could lead to the identification of novel antifungal drug targets.

Keywords: Candida albicans, Saccharomyces cerevisiae , Mitochondrial protein expression