Arl8b drives recruitment of LAMP1-positive membranes to mito-VPS41. (A) Confocal images of HeLa^VPS41KO cells cotransfected with Arl8b-GFP and mito-VPS41^WT-V5 or mito-V5 and immunolabeled for endogenous LAMP1 and V5. (B) Quantification of LAMP1 recruitment to mitochondria expressing mito-VPS41^WT-V5 or mito-V5 in the presence or absence of Arl8b-GFP (see also Fig. S2, F–J). Scatter plot data represent the mean ± SEM. Statistical significance was determined using Tukey’s multiple comparisons test. ****P < 0.0001, ***P < 0.001, ns: not significant. n ≥ 25. Scale bars: 10 µm. (C) Confocal images of endogenous LAMP1 in HeLa^WT cells, HeLa^Arl8a-bKO cells, or HeLa^Arl8a-bKO cells rescued with Arl8b-HA (bottom) expressing mito-VPS41^WT-GFP. (D) Quantification of mitochondrial redistribution of LAMP1 similar conditions as in C (see also Fig. S2 K). Data represent the mean ± SEM. Statistical significance was determined using an unpaired t test. ****P < 0.0001. n > 25. Scale bars: 10 and 5 µm (inset magnification).