Transfected and apoptotic cells. A fraction of cells exhibits extremely high C1D(EGFP)-dependent fluorescence when transfected with pcDNA3-C1D(EGFP). Cells belonging to this fraction can be distinguished by morphology and short exposure times required to capture 510 nm fluorescence mode images (about 100 milliseconds). Upper row: phase contrast mode; second row: DNA-specific fluorescence (456 nm); third row C1D(EGFP)-specific fluorescence (510 nm). Bars represent 10 μm.