Bright dimerized fluorogenic probes for imaging nucleic acids and proteins

Overview & Synopsis

Although dimerization is common process in protein biology enabling to discover new functionalities. Inspired by nature, we used dimerization approach to expand the toolbox of bright fluorogenic probes for selective imaging of live-cell biological events. The strategy was based on intramolecular self-aggregation of dyes, in particular homodimerization of the fluorophore via short linkage and tethered targeted ligand. We developed a family of fluorogens based of rhodamine scaffolds spanning their fluorescence from green to far-red region, named Gemini. In collaboration, we developed a bright photostable fluoromodule, Gemini-651/o-Coral, for RNA live-cell imaging. Systematic analysis of structure-activity relationship in dimerization probe design enabled the development of the probe for discrimination of cancer cells expressing biotin receptors on the cell surface. While being modular, dimerization-caused quenching approach provides bright activated fluorescence response of probes to biological event of interest. We showed its broad applicability in field of semisynthetic RNA/peptide-based technologies and targeted protein imaging. Further expansion of dimerized fluorogenic probes will significantly contribute to understanding the complexity of biological processes in living systems.