DOI: 10.1039/C5CC05208D
ChemComm
label EGFP-eDHFR_N23C/L28C-NLS in live cells (Figure S9).
These results showed that the introduced azido group is generally
ready for SPAAC reactions in live cells.
Notes and references
a
Chemical Genomics Centre of the Max Planck Society, Otto-Hahn-Str.
5, 44227 Dortmund, Germany. E-mail: yaowen.wu@mpi-
1
After successful demonstration of the “tagging-then-labeling”
approach in live cells, we proceeded to prove its utility in
visualizing intracellular processes (Figure 4a). Fluorescence
resonance energy transfer (FRET) is highly useful in cellular
biology to study protein-protein interactions in cells.
Fluorescence-lifetime imaging microscopy (FLIM) is an imaging
technique based on the measurement of the lifetime of the donor.
Energy transfer from the donor molecule to the acceptor molecule
will lead to a decrease in the fluorescence lifetime of the former,
dortmund.mpg.de
b
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Max-Planck Institute for Molecular Physiology, Otto-Hahn-Str. 11,
4
4227 Dortmund, Germany.
†
Electronic Supplementary Information (ESI) available: organic
synthesis, supporting figures and others. See DOI: 10.1039/b000000x/
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In conclusion, we have developed a versatile “tagging-then-
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Both the tagging and labeling reactions are fast. TMP-AcAz
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probes, including BCN- and DBCO-TAMRA and BCN-
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studies in live cells. We expect that the “tagging-then-labeling”
approach can be widely used for chemical protein labeling in
cells to study protein trafficking, protein-protein interactions,
proteomics and to elucidate various cellular processes.
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ACKNOWLEDGMENT
27. S. J. Falk, L. Y. Guo, N. Sekulic, E. M. Smoak, T. Mani, G. A.
Logsdon, K. Gupta, L. E. Jansen, G. D. Van Duyne, S. A.
Vinogradov, M. A. Lampson, and B. E. Black, Science, 2015, 348,
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25 28. D. Normanno, L. Boudarene, C. Dugast-Darzacq, J. Chen, C. Richter,
F. Proux, O. Benichou, R. Voituriez, X. Darzacq, M. Dahan, Nat.
Commun. 2015, 6, 7357.
We thank Philippe Bastiaens for the support in FLIM
measurements. We thank James C. Hu for the kind gift of the E.
coli. DHFR plasmid. This work was supported in part by DFG
grants (grant No.: SPP 1623 and SFB 642 to Y.W.W.).
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