Figure 3.

Observation of DLL4-Notch1 complexes using alternating epifluorescence-TIRFM. (A) Localization of the Notch1-eGFP at different time points is monitored with both epifluorescence and TIRFM (green), whereas DLL4 position is visualized in epifluorescence only (red). The highlighted cluster remains in the epifluorescence channel, but is diminished in TIRFM, suggesting translocation away from the membrane. Scale bar = 10 μm. (B) Waterfall plots indicate the changes in fluorescence intensity of the ligand-receptor complex (white arrow) as a function of time for each channel. To see this figure in color, go online.