Fig. 4

Mitochondrial apoptotic signaling pathway was activated by mtDNA injection (0.02 µg/µl, 2 µl). β-Actin was used as the loading control. VDAC1 was used as the internal control for mitochondrial proteins. A1 Western blotting of retinal BAK, BAX, cleaved caspase 9, cleaved caspase 3, and cytochrome c protein levels in the normal control group and mtDNA-transfected groups after 1, 3, 5, and 7 days. A2–A7 Western blotting analysis of cleaved caspase 3, cleaved caspase 9, BAK, BAX, cytochrome c in cytosolic and cytochrome c in mitochondrial. B1–B2 Real-time PCR was used to evaluate the transcription of Bax and Bak. *P < 0.05, **P < 0.01, n = 3 biological replicates in each group