Fig. 1. Identification of compounds that enhance the survival of Coq7 KO cells in galactose medium.

A Screening strategy. Primary screening of compound library was conducted with Coq7 KO mouse embryonic fibroblasts (MEFs) and test compounds that increase the survival of Coq7 KO cells in galactose medium were identified as screen hits. B OSI-027 and AZ20, two of the compounds identified in the screen, showed a positive effect on the survival of Coq7 KO cells in galactose medium. Cell viability was examined after 4-day culture in galactose medium. Phase-contrast microscopy images are shown on the left, and cell growth and survival measured by using the Crystal violet (CV) staining assay is on the right. DMSO is the vehicle control. C OSI-027 and AZ20 treatments cause no cell death but decrease CV staining. D OSI-027 or AZ20-treated Coq7 KO cells in galactose showed a lower CV staining intensity compared with the cells grown in glucose medium. The following doses were used in all experiments unless otherwise stated: OSI-027: 5 µM, AZ20: 10 µM, and CoQ₁₀: 10 µM, which was used as a positive treatment control. Scale bars = 100 µm. Data are presented as means ± SEM for n = 4–8. ***p < 0.001 and ****p < 0.0001, assessed by one-way ANOVA followed by Dunnett’s multiple comparison test or t-test versus the untreated or glucose-grown controls.