Poster abstracts

Poster number 11 submitted by Douglas Bernstein

Transcriptome-wide mapping reveals pseudouridylation as a dynamic process in budding yeast mRNA.

Douglas A. Bernstein (Biology, Ball State University ), Schraga Schwartz (Weizmann Institute of Science ), Maxwell R. Mumbach (Biology, Stanford), Gerald Fink (Biology, MIT), Aviv Regev (Biology, MIT)

Abstract:
Pseudouridylation is the most abundant post-transcriptional modification playing critical roles in RNA structure and function in all kingdoms of life. While numerous pseudouridylation sites in noncoding RNAs have been mapped, quantitative assessment of pseudouridine transcriptome-wide has been technically impractical. We have developed a novel pseudouridine sequencing technique that maps and quantitatively measures pseudouridylation transcriptome-wide. Pseudouridine sequencing has identified hundreds of novel pseudouridines in mRNAs. These modifications are dependent upon specific pseudouridine synthases, and occur at consensus motifs. Previous data indicated that pseudouridylation is induced in S. cerevisiae snRNAU2 by stress. We used pseudouridine sequencing to assess pseudouridylation transcriptome wide under a variety of stress conditions. We find pseudouridylation levels change significantly at a number of sites in noncoding RNAs during cold and nutrient stresses. During heat stress however, pseudouridylation is induced at over two hundred sites in mRNA. The majority of these modifications are dependent on the pseudouridine synthase Pus7, and occur at a Pus7 consensus motif. In addition, PUS7 deletion renders S. cerevisiae heat sensitive and Pus7 localization changes in response to heat stress suggesting Pus7 facilitated pseudouridylation is important for heat shock survival, and Pus7 localization plays a role mediating mRNA pseudouridylation during heat stress. In conclusion we have mapped pseudouridine transcriptome-wide, and we find pseudouridylation to be a dynamic process important for yeast stress response.

Keywords: pseudouridine, post-transcriptional modification , Pus7