Poster abstracts

Poster number 58 submitted by Yizhou Xie

Interesting Properties of Pus10, a Pseudouridine Synthase of Eukaryotes and Archaea

Yizhou Xie (University of Louisville, Department of Chemistry, Louisville, KY 40292), Eugene G. Mueller (University of Louisville, Department of Chemistry, Louisville, KY 40292)

Abstract:
Pseudouridine synthases isomerize uridine (U) to its C-glycoside isomer, pseudouridine (Ψ) in RNA. Based on sequence and structural similarity, six families of Ψ synthases have been identified, which are typically named after their first cloned member: TruA, TruB, RluA, RsuA, TruD, and Pus10 [1]. Pus10, a member of the most recently identified Ψ synthase family isomerizes U55 in archaeal tRNAs [2] and also transforms the adjacent U54 to Ψ54 [3].

This work examines the activity of Methanococcus jannaschii Pus10 towards both U55 and U54 in stem-loop RNA substrates. The radiolabeling/TLC method used in a previous study [2-3] has been replaced by a less cumbersome HPLC method. Pus10 clearly isomerizes U55 more efficiently than U54. The temperature dependence of the reaction rates and preliminary kinetic data are also presented.

References:
1. Mueller, E. G., and Ferré-D'Amaré, A. R. (2009) Pseudouridine Formation, the Most Common Transglycosylation in RNA, In DNA and RNA Modification Enzymes: Structure, Mechanism, Function and Evolution (Grosjean, H., Ed.).
2. Roovers, M., Hale, C., Tricot, C., Terns, M. P., Terns, R. M., Grosjean, H., and Droogmans, L. (2006) Formation of the conserved pseudouridine at position 55 in archaeal tRNA, Nucleic Acids Res 34, 4293-4301.
3. Gurha, P., and Gupta, R. (2008) Archaeal Pus10 proteins can produce both pseudouridine 54 and 55 in tRNA, RNA 14, 2521-2527.

Keywords: Pseudouridine synthases , Pus10, HPLC method