Figure 2

Reduced mitochondrial transmembrane potential in PINK1 −/− cells. A. Representative confocal microscopic images of PINK1−/− and +/+ MEFs after staining with TMRM (50 nM, red) and Mitotracker Green (200 nM) in the presence or absence of oligomycin (Olig, 1 μM) or FCCP (10 μM). The intensity of TMRM reflects the level of mitochondrial transmembrane potential, whereas the intensity of Mitotracker Green is not affected by transmembrane potential. The bottom right inserts are the higher power views of the boxed areas in the same panel. The TMRM signal is reduced in PINK1−/− cells, whereas the TMRM signal is increased and decreased similarly in both PINK1−/− and +/+ cells following oligomycin and FCCP treatment, respectively. B. The bar graph shows quantification of TMRM signals in PINK1−/− and +/+ MEFs in the presence or absence of oligomycin and FCCP using confocal images. The number shown in the panel indicates the number of cells used in the study. C. Representative flow cytometry dot plots show the intensity of TMRM signals in PINK1−/− and +/+ MEFs following incubation with TMRM (50 nM) in the presence or absence of oligomycin (1 μM) or FCCP (10 μM). D. The bar graph shows quantification of TMRM signals measured by FACS analysis in PINK1−/− and +/+ MEFs. The number shown in the panel indicates the number of independent experiments performed. E. The bar graph of TMRM fluorescent signals in PINK1−/− and +/+ neurons shows reduced TMRM signals in PINK1−/− neurons. The numbers shown indicate the number of neurons used (left) and the number of independent experiments performed (right) in the study. All data are expressed as mean ± SEM. Scale bar: 10 μm. * p < 0.05, ** p < 0.01, *** p < 0.001.