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Updated: May 14, 2026
11:21
Photoconversion of Purified Fluorescent Proteins and Dual-probe Optical Highlighting in Live Cells
Published on: June 26, 2010
Targeted Green-Red Photoconversion of EosFP, a Fluorescent Marker Protein
Sergey Ivanchenko1, Carlheinz Röcker, Franz Oswald
1Department of Biophysics, University of Ulm, 89069 Ulm, Germany.
Journal of Biological Physics
|January 25, 2013
Summary
EosFP, a novel fluorescent protein from Lobophyllia hemprichii coral, exhibits green fluorescence that shifts to red after UV light exposure. Researchers developed variants and demonstrated its use in tracking cellular processes.
Area of Science:
- Biochemistry
- Molecular Biology
- Biophysics
Background:
- Fluorescent proteins are essential tools in biological research.
- Novel fluorescent proteins with unique photophysical properties are continuously sought.
- EosFP is a newly discovered fluorescent protein from the stony coral Lobophyllia hemprichii.
Purpose of the Study:
- To characterize the spectroscopic properties of EosFP and its variants.
- To investigate the mechanism of photo-induced spectral switching.
- To demonstrate the utility of EosFP for live-cell imaging applications.
Main Methods:
- Gene cloning and expression of EosFP in Escherichia coli.
- Site-directed mutagenesis to create dimeric and monomeric variants.
- Spectroscopic analysis including room- and low-temperature measurements, fluorescence lifetime, and two-photon excitation/photoconversion.
- Cell transfection with EosFP fusion constructs for intracellular imaging.
Main Results:
- EosFP exhibits strong green fluorescence (516 nm) that photoconverts to red fluorescence (581 nm) upon near-UV irradiation (390 nm).
- Photo-induced modification involves a peptide backbone break adjacent to the chromophore.
- Dimeric and monomeric variants (d1EosFP, d2EosFP, mEosFP) were generated with preserved spectroscopic characteristics.
- Localized photoconversion in HeLa cells demonstrated potential for resolving intracellular dynamics.
Conclusions:
- EosFP is a versatile photoactivatable fluorescent protein with tunable variants.
- Its photo-induced switching mechanism provides a basis for advanced imaging techniques.
- EosFP and its variants offer valuable tools for studying dynamic biological processes in living cells.
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