5-Vinyl-uridine (5-VU)

5-VU (5-Vinyl-uridine) can potentially be used as a replacement for BrU (5-Bromo-uridine) or the copper-catalyst requiring 5-EU (5-Ethynyl-uridine) to measure de novo RNA synthesis in proliferating cells. 5-VU is cell permeable and might incorporate into nascent RNA instead of its natural analog uridine. This assumption is based on the previously demonstrated suitability of 5-VdU (5-Vinyl-2'-deoxyuridine) for DNA synthesis monitoring. The resulting vinyl-functionalized RNA could subsequently be detected via Cu (I) -free Alkene-Tetrazine Ligation that offers the choice to introduce a Biotin group (via Tetrazines of Biotin) for subsequent purification tasks or a fluorescent group (via Tetrazines of fluorescent dyes) for subsequent microscopic imaging.