FIGURE 5.

Fluorescence emission of Cerulean-Bsn1692-3263 in the absence and presence of Citrine-CtBP1 in living COS-7 cells. (a) Comparison of fluorescence emission spectra of Cerulean-Bsn1692-3263 (black) with the FRET sample (shading). A significant Citrine enhancement was observed in the presence of FRET. (b) Fluorescence decay of Cerulean-Bsn1692-3263 in the FRET sample (shading) was shorter compared to the control (black). IRF is shown in light shading. (c) DAS of control Cerulean-Bsn1692-3263. The preexponential factors of lifetimes τ₁ (solid), τ₂ (shading), and τ₃ (light shading) were plotted along the wavelength (Table 1). (d) Mean lifetimes of each emission band were plotted along the wavelength for Cerulean-Bsn1692-3263. The variability between the cells is represented by error bars, which shows deviation due to the aggregating nature of the construct. (e) DAS of the FRET sample, Cerulean-Bsn1692-3263+Citrine-CtBP1. The preexponential factors of lifetimes τ₁ (solid), τ₂ (shading), and τ₃ (light shading) (see Table 1) were plotted along the wavelength. Negative amplitudes were observed for τ₂ at the acceptor emission maximum in the presence of FRET. (f) Mean lifetimes of each emission band were plotted with error bars along the wavelength for the FRET sample.