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bioRxiv · 10.1101/2024.10.21.619086

Temporal placement of RNA modifications under 5-fluorouracil treatment in human cell culture

Berg, M.·Li, C.·Kaiser, S.
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Abstract

Recent studies have explored the dynamic changes in RNA modification across various organisms, often in response to stressors like chemical agents or drugs. Among these, the anticancer drug 5-fluorouracil (5-FU) has been evaluated regarding its impact on RNA and DNA. Although different alterations in RNA modification have been associated with 5-FU, a mechanistic insight into the dynamic effects on RNA modification is missing. In this study, we provide a detailed insight into the dynamic modification changes for tRNA and rRNA of HEK293T cells exposed to 5-FU using Nucleic Acid Isotope Labeling coupled Mass Spectrometry (NAIL-MS). Consistent with existing literature, we observed a constant loss of m5U in newly transcribed tRNA during 5-FU exposure. In addition to m5U, we identified a loss of m5Um and an increase of Um within tRNALysUUU. While cells recover from a 24-hour 5-FU treatment, we found changed abundances of modifications like an increase of mcm5U and m5C and a decrease of m7G and m1A in total tRNA. Moreover, we demonstrate that 5-FU affects various rRNA subtypes, altering both their modification stoichiometry and abundance. Taken together, we use NAIL-MS to deconvolute RNA modification abundance changes caused by drug treatment and we uncover patterns of RNA modification adaptation.

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Berg, M., Li, C., Kaiser, S.. 2024-10-24. Temporal placement of RNA modifications under 5-fluorouracil treatment in human cell culture. https://doi.org/10.1101/2024.10.21.619086

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