Figure 2

FRET evaluation of ECF-HIF-1α and EYFP-HIF-1β interaction. Osteosarcoma cells U-2OS were transfected with plasmids expressing the donor molecule ECFP-HIF-1α and the acceptor EYFP-HIF-1β. 48 h later cells were scanned for fluorescence and FRET was determined. The black curve indicates random FRET values as described in detail in Figure 3. Red filled circles show FRET efficiency values from individual cells which result in mean FRET efficiency for HIF-1α/HIF-1β as indicated by the red curve.