FIGURE 8.

Fluorescence emission dynamics of Cerulean-Bsn1692-3263 in the absence (n = 8) and presence (n = 5) of Citrine-CtBP1 at synapses of living neurons at DIV 16. (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 than the control (black). IRF is shown in light shading. (c) DAS of Cerulean-Bsn1692-3263 in living neurons. The preexponential factors of lifetimes τ₁ (solid) and τ₂ (shading) (see Table 3) were plotted along the wavelength. The preexponential factors showed only positive values. (d) Mean lifetimes of each emission band of Cerulean-Bsn1692-3263 was plotted along the wavelength. No deviations along the spectra were observed. (e) DAS of the FRET sample, Cerulean-Bsn1692-3263+Citrine-CtBP1. The preexponential factors of lifetimes τ₁ (solid), τ₂ (shading), and τ₃ (light shading) (Table 3) were plotted along the wavelength. Negative amplitudes were observed for τ₂ at the acceptor emission maximum in the presence of FRET. (f) The plot of mean lifetimes showed significant deviations along the wavelength in the presence of FRET.