Fig. 5: Effects of Parkin knockout on VDAC1 oligomerization and ubiquitination.

a Representative immunoblots of VDAC1 monomer and oligomers in mouse livers. The crosslinking reagent EGS was used to stabilize the oligomers during electrophoresis. b Representative immunoblots of ubiquitinated VDAC1 in mouse livers. c Quantitative histogram of VDAC1 oligomers (n = 11-14/group). Quantitative histogram of (d) total VDAC1 in whole cell lysate (WCL) (GAPDH as the loading control) (n = 5/group) and (e) the ratio of ubiquitinated to total VDAC1 after IP with anti-VDAC1 antibody (n = 5/group). (f) Pearson correlation coefficient of dsDNA outside the nucleus and mitochondria (n = 9/group). siRNA targeting ENDOG, a nuclear-encoded mitochondrial endonuclease, was employed to induce mtDNA release in HepG2 cells. g Representative immunofluorescence images of cytosolic DNA accumulation in WT and ENDOG-knockdown HepG2 cells transfected or not transfected with Parkin using anti-dsDNA antibody (green) and MitoTracker (red). DAPI (blue) represents nuclear DNA, the yellow dots in the merged images represent mtDNA (dsDNA colocalized with MitoTracker), and the green dots in the merged images represent cytosolic DNA (dsDNA not colocalized with mitochondria or the nucleus). Mean ± SEM, *p < 0.05, **p < 0.01, ***p < 0.001 and **** p < 0.0001 between the indicated groups.