Fig. 4

Endogenous formation of persulfides in HEK293T cells. Intracellular levels of CysSSH (a) and GSSH (b) in WT and CARS2 KO cells with CARS1 or CARS2 knocked down. Data are means ± s.d. (n = 3). *P < 0.05; **P < 0.01; N.S., not significant. c CARS1 and CARS2 Western blotting for cells used in a and b. Lane 1 and 2, duplicate determinations with each siRNA. The right panel shows the densitometric analysis for the western blot shown in the right panel. The data are means ± s.d. (n = 3). ***P < 0.001. Production of CysSSH (d) and GSSH (e) in CARS2 KO cells with WT or CARS2 C and K mutants added back. The data are means ± s.d. (n = 3). **P < 0.01; N.S., not significant vs. CARS2 KO mock. f CARS2 western blotting for WT and CARS2 KO cells with WT or CARS2 C and K mutants added back. g Western blotting for the cells in d and e with different mitochondrial proteins: MTCO1, mitochondrial cytochrome c oxidase subunit 1 (encoded by mitochondrial DNA) and SDHA, succinate dehydrogenase complex flavoprotein subunit A (encoded by genomic DNA). Supplementary Fig. 16 provides full blot images. The lower panel shows the densitometric analysis for the western blot. The data are means ± s.d. (n = 3). ***P < 0.001