Loss of DJ-1 Does Not Affect Mitochondrial Respiration but Increases ROS Production and Mitochondrial Permeability Transition Pore Opening
Figure 4
Reduced mitochondrial membrane potential (ΔΨm) in DJ-1−/− MEFs.
(A, B) Confocal microscopic analysis. (A) Representative confocal microscopic images of DJ-1−/− 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 ΔΨm, whereas the intensity of Mitotracker Green is not affected by transmembrane potential. Insets in panels indicate higher power views of the boxed area. Scale bar: 10 µm. (B) The bar graph shows quantification of TMRM signal in DJ-1−/− and +/+ MEFs in the presence or absence of oligomycin or FCCP. The TMRM signal is reduced in DJ-1−/− cells relative to wild-type cells, whereas the TMRM signal is increased or decreased in both DJ-1−/− and +/+ cells following oligomycin or FCCP treatment, respectively. The number shown in the panel indicates the number of cells quantified per genotype in the study. (C, D) FACS analysis. (C) Representative flow cytometric dot plots show the intensity of TMRM signal in DJ-1−/− 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 signal measured by FACS analysis in DJ-1−/− and +/+ MEFs. The number shown in the panel indicates the number of embryos used to derive primary MEFs per genotype, and the data were obtained from five independent experiments. All data are expressed as mean ± SEM. **p<0.01, ***p<0.001.