Intracellular and Intercellular Signalling Mechanisms following DNA Damage Are Modulated By PINK1

Figure 3

PINK1 role in the intracellular response to genotoxic stress due to BLM. Treatment of MEFs with 40 μg/mL BLM induces decreased viability as assessed by the MTS test and nuclear morphology (a, b), increased activation of caspases as executors of programmed cell death (c), and increased accumulation of ROS (d). The ATP level and mitochondrial potential as measures of mitochondrial function remained unmodified following the treatment with BLM (e, f); however, the basal ATP and mitochondrial levels are diminished in the cells with PINK1 loss of function. The data is reported as percentage of WT untreated control or fold change versus WT untreated control. Each data point represents the mean ± SEM of at least three independent experiments. Statistical analysis is performed with two-way ANOVA with multiple comparisons, and values are indicated in the figure. (g) Analysis of respiratory activity shows that such activity is reduced in the cells with PINK1 loss of function. The respiratory activity was determined using specific substrates and inhibitors for complex I- and II-linked respiration in the presence of ADP. Maximum respiration and ETS were achieved by uncoupling mitochondria with CCCP. ETS excess capacity was calculated by subtracting complex I + II-linked flux from maximum respiration. Each data point represents the mean ± SEM of three independent experiments. Statistical significance was determined with Student’s t-test. .

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