Modulation of the matrix redox signaling by mitochondrial Ca2+

Figure 2 Ratiometric fluorescence intensity response of roGFP1 to histamine stimulation and exogenous H₂O₂ and DL-dithiothreitol in living HeLa cells. HeLa cells were transfected with the mitochondrial targeted redox sensor roGFP1. Cells were excited at 410 and 480 nm and emission was collected at 535 nm. The 410/480 fluorescence ratio (R) was normalized to the minimum of fluorescence (obtained after the addition of 1 mmol/L H₂O₂) and the maximum (after the addition of 10 mmol/L dithiothreitol, DL-dithiothreitol). The effect of intracellular Ca²⁺ was assessed by stimulating the cell with 100 μmol/L histamine. DTT: DL-Dithiothreitol.