Fig. 3.

Mitophagy is Enhanced by Reduced Cav-1 Expression. MDA-MB-231 cells treated with control siRNA (CTL), Cav-1 siRNA (SI), or Cav-1 adenovirus (AD) to rescue Cav-1 expression for 48–72 h were stained with 50 nM TMRM for 30 min at 37 °C and visualized by confocal microscopy.

(A) Quantification of TMRM revealed a 35% reduction in mitochondrial mass in Cav-1 siRNA treated cells.

(B) CTL, SI and AD cells transfected with mito-Keima for 48 h were visualized by confocal microscopy. The mito-Keima signal was captured by alternating 458 nm and 561 nm excitation and emitted fluorescence expressed as a ratio of 561/458 was used to reflect mitophagy. Bar graph depicts the fold change in 561/458 fluorescence relative to control. Cav-1 SI induced a 3-fold increase in the 561/458 fluorescence ratio compared with control and Cav-1 reconstituted cells.

(C) The fluorescence signal of TMRM recovered by 60% after 4 μM antimycin and 10 μM oligomycin insult as compared to 40% recovery in control and Ad-Cav-1 rescued cells. Data are mean ± SEM, n ≥ 10; ***p < 0.001 vs control by ANOVA.