TY - JOUR
T1 - Far-red light photoactivatable near-infrared fluorescent proteins engineered from a bacterial phytochrome
AU - Piatkevich, Kiryl D.
AU - Subach, Fedor V.
AU - Verkhusha, Vladislav V.
N1 - Funding Information:
We thank E. Giraud for the AtBphP2 gene, J. Zhang and L. Tesfa for their assistance with flow cytometry, Y. Wang and L.-M. Ting for their help with mouse experiments and G. Filonov for the useful discussions. This work was supported by the grants GM073913, CA164468 and EB013571 from the National Institutes of Health.
PY - 2013
Y1 - 2013
N2 - The ability to modulate the fluorescence of optical probes can be used to enhance signal-to-noise ratios for imaging within highly autofluorescent environments, such as intact tissues and living organisms. Here, we report two bacteriophytochrome-based photoactivatable near-infrared fluorescent proteins, named PAiRFP1 and PAiRFP2. PAiRFPs utilize haem-derived biliverdin, ubiquitous in mammalian tissues, as the chromophore. Initially weakly fluorescent PAiRFPs undergo photoconversion into a highly fluorescent state with excitation/emission at 690/717 nm following a brief irradiation with far-red light. After photoactivation, PAiRFPs slowly revert back to initial state, enabling multiple photoactivation-relaxation cycles. Low-temperature optical spectroscopy reveals several intermediates involved in PAiRFP photocycles, which all differ from that of the bacteriophytochrome precursor. PAiRFPs can be photoactivated in a spatially selective manner in mouse tissues, and optical modulation of their fluorescence allows for substantial contrast enhancement, making PAiRFPs advantageous over permanently fluorescent probes for in vivo imaging conditions of high autofluorescence and low signal levels.
AB - The ability to modulate the fluorescence of optical probes can be used to enhance signal-to-noise ratios for imaging within highly autofluorescent environments, such as intact tissues and living organisms. Here, we report two bacteriophytochrome-based photoactivatable near-infrared fluorescent proteins, named PAiRFP1 and PAiRFP2. PAiRFPs utilize haem-derived biliverdin, ubiquitous in mammalian tissues, as the chromophore. Initially weakly fluorescent PAiRFPs undergo photoconversion into a highly fluorescent state with excitation/emission at 690/717 nm following a brief irradiation with far-red light. After photoactivation, PAiRFPs slowly revert back to initial state, enabling multiple photoactivation-relaxation cycles. Low-temperature optical spectroscopy reveals several intermediates involved in PAiRFP photocycles, which all differ from that of the bacteriophytochrome precursor. PAiRFPs can be photoactivated in a spatially selective manner in mouse tissues, and optical modulation of their fluorescence allows for substantial contrast enhancement, making PAiRFPs advantageous over permanently fluorescent probes for in vivo imaging conditions of high autofluorescence and low signal levels.
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U2 - 10.1038/ncomms3153
DO - 10.1038/ncomms3153
M3 - Article
C2 - 23842578
AN - SCOPUS:84880296970
SN - 2041-1723
VL - 4
JO - Nature communications
JF - Nature communications
M1 - 2153
ER -