Recently, a different innovative ratiometric probe - a redox-sensitive GFP (roGFP) - has been developed in another lab. The measurement with the roGFP sensor involves the ratio of intensities of two sequential images, acquired at two different excitation wavelengths. Two thiol groups form/break a disulfide bond that modulates the peak excitation wavelength of the roGFP chromophore in response to the redox environment. Bryan Spring, a co-author, notes, "The roGFP and the FRET-based sensors have contrasting characteristics. The FRET-based sensor may prove advantageous for intravital microscopy studies, because only a single laser line is required. In contrast, roGFP requires sequential scanning of two laser lines, which slows the frame rate of image acquisition; also, the images must be compensated for the different laser intensities in order to correct for wavelength-dependent tissue scattering, and the measurement relies on the optical alignment of two excitation light beams. However, the roGFP probe is sensitive to a different range of oxidation-reduction potentials than our FRET probe, possibly leading to complementary applications." Spring adds, "We look forward to further exciting innovations for optimizing the performance of oxidation-reduction-based sensors."
Dr. Rex Gaskins, who led the project remarked, "Distinct advantages of the FRET-based approach include: (1) the ability to quantify the change in redox state; (2) independence of sensor concentration; and (3) modularity, the ability to precisely tune the redox sensitivity and range by exchange of the switch or the fluorophore modules in the probe. We expect that newly developed redox-sensitive probes could potentially be critical to a better
|Contact: Vladimir L. Kolossov|
Society for Experimental Biology and Medicine