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Beadle, L. F.

Publications and source records attributed to Beadle, L. F..

3 recordsLinked to original sources

AquIRE reveals multiple mechanisms of clinically induced RNA damage and the conservation and dynamics of glycoRNAs

RNA is subject to many modifications, from small chemical changes such as methylation through to conjugation of biomolecules such as glycans. As well as these endogenously written modifications, RNA is also exposed to damage induced by its environment. Certain clinical compounds are known to drive covalent modifications of RNA with a growing appreciation for how these affect function. To understand the regulation of these modifications we need a reliable, sensitive and rapid methodology for their quantification. Thus, we developed AquIRE and applied it to the analysis of drug-induced RNA damage, showing this to be widespread with intricate temporal dynamics. Using the same methodology we identify RNA:protein crosslinking and the rewriting of the epitranscriptome as a consequence of clinical RNA damage. We also demonstrate how liquid-liquid phase separation increases RNA damage and expand the horizons of the glycoRNA world across the kingdoms of life and into cell-free glycoRNA.

molecular biology↗

Spatially regulated mRNA decay sharpens expression patterns in the Drosophila embryo

The regulation of mRNA decay is important for numerous cellular and developmental processes. Here, we use the patterning gene even-skipped (eve) in the early Drosophila embryo to investigate the contribution of mRNA decay to shaping the mature striped expression pattern. Using mathematical models to analyse live and fixed imaging data, we show that for eve stripes 2 and 4, spatially regulated degradation rates outperform models with constant or mRNA age-dependent decay. Uniform mRNA decay rates perturb definition of eve stripes 2 and 4 in silico, and we show that altering eve mRNA numbers in vivo by changing the UTR results in dysregulation of the anterior-posterior pair-rule network and embryo segmentation defects. Overall, these data demonstrate how eve mRNA instability can function with transcriptional regulation to define sharp expression domain borders. We suggest that spatially regulated mRNA stability may be widely used to sculpt expression patterns during development.

developmental biology↗

A simple MiMIC based approach for tagging endogenous genes to visualise live transcription in vivo

Live imaging of transcription in the Drosophila embryo using the MS2 or PP7 systems is transforming our understanding of transcriptional regulation. However, insertion of MS2/PP7 stem loops into endogenous genes requires laborious CRISPR genome editing. Here we exploit the previously described Minos-mediated integration cassette (MiMIC) transposon system in Drosophila to establish a method for simply and rapidly inserting MS2/PP7 cassettes into any of the thousands of genes carrying a MiMIC insertion. In addition to generating a variety of stem loop donor fly stocks, we have made new stocks expressing the complementary coat proteins fused to different fluorescent proteins. We show the utility of this MiMIC-based approach by MS2/PP7 tagging and live imaging transcription of endogenous genes and the long non-coding RNA, roX1, in the embryo. We also present live transcription data from larval brains, the wing disc and ovary, thereby extending the tissues that can be studied using the MS2/PP7 system. Overall, this first high throughput method for tagging mRNAs in Drosophila will facilitate the study of transcription dynamics of thousands of endogenous genes in a range of Drosophila tissues.

developmental biology↗