Bioorthogonal labeling with tetrazine-dyes forsuper-resolution microscopy

Beliu, G.; Kurz, A.; Kuhlemann, A.; Behringer-Pliess, L.; Wolf, N.; Seibel, J.; Shi, Z.-D.; Schnermann, M.; Grimm, J.; Lavis, L.; Doose, S.; Sauer, M.

doi:10.1101/503821

bioRxiv · 10.1101/503821

Bioorthogonal labeling with tetrazine-dyes forsuper-resolution microscopy

Beliu, G.·Kurz, A.·Kuhlemann, A.·Behringer-Pliess, L.·Wolf, N.·Seibel, J.·Shi, Z.-D.·Schnermann, M.·Grimm, J.·Lavis, L.·Doose, S.·Sauer, M.

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Abstract

Genetic code expansion (GCE) technology allows the specific incorporation of functionalized noncanonical amino acids (ncAAs) into proteins. Here, we investigated the Diels-Alder reaction between trans-cyclooct-2-ene (TCO)-modified ncAAs, and 22 known and novel 1,2,4,5-tetrazine-dye conjugates spanning the entire visible wavelength range. A hallmark of this reaction is its fluorogenicity - the tetrazine moiety can elicit substantial quenching of the dye. We discovered that photoinduced electron transfer (PET) from the excited dye to tetrazine as the main quenching mechanism in red-absorbing oxazine and rhodamine derivatives. Upon reaction with dienophiles quenching interactions are reduced resulting in a considerable increase in fluorescence intensity. Efficient and specific labeling of all tetrazine-dyes investigated permits super-resolution microscopy with high signal-to-noise ratio even at the single-molecule level. The different cell permeability of tetrazine-dyes can be used advantageously for specific intra- and extracellular labeling of proteins and highly sensitive fluorescence imaging experiments in fixed and living cells.

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Beliu, G., Kurz, A., Kuhlemann, A., Behringer-Pliess, L., Wolf, N., Seibel, J., Shi, Z.-D., Schnermann, M., Grimm, J., Lavis, L., Doose, S., Sauer, M.. 2018-12-21. Bioorthogonal labeling with tetrazine-dyes forsuper-resolution microscopy. https://doi.org/10.1101/503821

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