Metabolic labeling of DNA and RNA by means of synthetic and bioorthogonally reactive nucleosides as fluorogenic probes in living cells

• Applicant: Professor Dr. Hans-Achim Wagenknecht
• Subject Area: Biological and Biomimetic Chemistry
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 461961063

In order to study biological processes of nucleic acids in their natural environment, the biological cells, they must be labeled with fluorescent probes. Metabolic labeling of DNA and RNA is the appropriate chemical-biological method for this purpose. In this project, the metabolic labeling of RNA will be combined with the metabolic labeling of DNA. The Diels-Alder reaction with inverse electron demand for RNA and the photoclick reaction will be used as orthogonal and bioorthogonal reactions for DNA. For both reactions, differently substituted cyclopropenyl groups are used as bioorthogonal reactive functions because they offer the best compromise between size, ring strain and reactivity. A small library of cyclopropenylated nucleosides and 2'-deoxynucleosides is therefore to be synthesized and evaluated via the reaction kinetics. For the metabolic labeling of DNA, the photoclick reaction with visible light must be further developed for use in water. To this end, dye-tetrazole conjugates are to be synthesized and investigated photochemically. The metabolic labeling of RNA using the Diels-Alder reaction with inverse electron demand is to be developed into fluorogenic probes. These can be combined with FISH probes via energy transfer to enable the imaging of RNA transcripts not only in fixed cells but also in living cells.

• DFG Programme: Research Grants