Poster abstracts

Poster number 68 submitted by Tulsi Bhandari

Analysis of photo-oxidation induced products of post-transcriptional modifications in tRNA using LC-MS/MS technique

Tulsi Bhandari (Department of Chemistry, University of Cincinnati), Balasubrahmanyam Addepalli (Department of Chemistry, University of Cincinnati), Patrick A. Limbach (Department of Chemistry, University of Cincinnati)

Translation function is highly dependent on the post-transcriptional modifications (PTM) on tRNA molecule. PTM play crucial role in maintaining the structure, stability, and function of tRNA molecules. Absence or aberrant presence of PTM at different position in RNA has been linked with diseases including cancer. It has been proved that UVA rays as exogenous source of reactive oxygen species affected PTMs in tRNA molecules causing oxidative degradation of PTMs. Literature tends to serve the knowledge that ribonucleosides undergo photo reaction to give photoproducts, it is not well studied about the conversion products of all the PTMs that degrades after UVA exposure. By using Neutral Loss Scan (NLS) technique of mass-spectrometry, we unearthed photoproducts of some modified ribonucleosides produced after photosensitizer induced UV damage, and with the tools like stable isotope labelling, high mass accuracy LC-MS/MS, and spectral matching we did the structural characterization. We intend to probe into biological significance of such photoproducts detected.

Keywords: post-transcriptional modifications, tRNA, UVA rays, oxidative degradation, Neutral Loss Scan, spectral matching, LC-MSMS