Fig 2: Expression of mitochondrial dynamics regulatory proteins in Sigmar1−/− mouse hearts at 6 months of age. A, Representative Western blot and (B) densitometric quantification of the expression of mitochondrial dynamic regulatory proteins in the whole‐cell fraction of Wt and Sigmar1−/− hearts: pDrp1 Ser637, pDrp1 Ser616, Drp1, and OPA1. C, Representative Western blot and (D) densitometric quantification of the expression of mitochondrial dynamic regulatory proteins in the mitochondrial fraction of Wt and Sigmar1−/− hearts: Drp1 and OPA1. Drp1‐overexpressing HEK293 cells were used as a positive control for Drp1, and β‐actin was used on the same membrane. The cytosol fraction was used as a positive control to confirm GAPDH detection. COXIV was used on the same membrane, confirming the mitochondrial extracts. Ponceau S protein staining of the transfer membrane confirmed approximately equal loading and transfer across the gel (n=5‐6 mice per group). P values were determined by Tukey post hoc test. Boxes represent interquartile ranges, lines represent medians, whiskers represent ranges, and P values were determined by a Kruskal‐Wallis test. NS indicates not significant; Wt, wild type.

Fig 3: MnTE-2-PyP maintained mitochondrial homeostasis after radiation and hyperglycemia stress in normal prostate fibroblasts. Human prostate fibroblast cells were treated with 20 mM glucose (HG) and 30 μM MnTE-2-PyP (T2E) followed by 3 Gy of X-rays (RAD). 5 days after radiation, cells were harvested. Mitochondrial and cytosolic proteins were extracted. A. Representative western blots for DRP1 (mitochondrial fission protein), MFN1, MFN2 and OPA1 (mitochondrial fusion proteins) were measured and quantified. B. Quantification of PGAM5 in the cytosolic protein extract were measured. C. Cells were harvested at 30 h and 5 days post radiation. PINK1 protein levels were quantified in mitochondrial protein extracts. All images and graphs are representative of at least 3 independent experiments. CON = control, HG = high glucose, T2E = 30 μM MnTE-2-PyP treated, TG = T2E + HG treated, RAD = 3 Gy X-ray treated, RG = RAD + HG treated, RT = RAD + T2E treated and RGT = RAD + HG + T2E treated.(*), ($), (#) and (@) denote a significant difference (p ≤ 0.5) as compared to control, HG, RAD and RAD + HG group respectively.

Fig 4: Computational proof-of-principle that cancers with altered mitochondrial dynamics exhibit differential drug sensitivity. a Top, pie charts in five major cancer types summarizing the percentage of tumors with amplifications in DNM1L, OPA1, MFF, MFN1, MFN2, or FIS1, using publicly available data from the TCGA. Bottom, bar graphs summarizing the percentage of amplifications in each of the six genes from above. b The number of drugs from a dataset of 265 drugs with statistically significant differences in sensitivity when cell lines of a given cancer type are stratified based upon amplification status of each of the six genes listed above making sure to control for amplifications in neighboring oncogenes. c Examples of the drug sensitivity differences from b in DNM1L amplified breast cancer. d Four drugs from c are shown to illustrate the differences in drug sensitivity between DNM1L-amplified breast cancer vs. wild-type breast cancer. *p < 0.05 by Welch’s t-test. AUC area under the curve for the drug sensitivity assay

Fig 5: Bivariate correlational analysis for gene expression of (a) DRP1, (b) PINK1 and the protein expression of (c) OPA1, (d) PINK1, and (e) Parkin with testosterone area under the curve. The average of 12 and 24 h were used for gene and protein expression in correlational analyses