Deletion of UBXD8 perturbs peroxisome abundance. (A) HeLa WT and UBXD8 KO cells were stained for peroxisomes using peroxisomal matrix marker catalase. (B) Quantification of average peroxisome per cell and average peroxisome size from A. At least 100 cells were analyzed in N = 3 independent experiments. The violin plot shows median and 95% confidence intervals. ****P < 0.0001, unpaired t test. (C) HeLa WT and UBXD8 KO cells stained for peroxisomes using PMP70. (D) Quantification of peroxisomes per cell and peroxisome size in C. 50–100 cells were analyzed in N = 3 independent experiments. The violin plot shows median and 95% confidence intervals. ****P < 0.0001, unpaired t test. (E) HeLa cells were transfected with control and two different UBXD8 siRNAs and stained for catalase. (F) Quantification of peroxisomes per cell and peroxisome size from E. 50–100 cells were analyzed in N = 3 independent experiments. The violin plot shows median and 95% confidence intervals. ns: not significant, ***P < 0.001, ****P < 0.0001, unpaired t test. (G) Immunoblot showing UBXD8 depletion. (H) Overexpression of UBXD8 increases peroxisomes in WT HeLa cells. WT HeLa cells were transfected with UBXD8-HA and stained for catalase. (I) Quantification of peroxisomes per cell in WT, UBXD8 KO, and WT transfected with UBXD8-HA. 50–100 cells were analyzed in N = 3 independent experiments. The violin plot shows median and 95% confidence intervals. *P < 0.0169, ****P < 0.0001, two-way ANOVA with Dunnett’s multiple comparisons test, two-way ANOVA. (J) Immunoblot of UBXD8-HA expression. The scale bar is 10 μM (A, C, and H) and 5 μM (E). Source data are available for this figure: SourceData F2.