Supplementary Figure 13: MIRO1-induced peroxisomal membrane protrusions depend on PEX11β.

(a-h) PEX5-deficient human skin fibroblasts were mock-treated (control), or transfected with Myc-Miro-PO, a peroxisome-targeted Miro1 variant, in the presence of control- or PEX11β-specific siRNA. Cells were processed for immunofluorescence using anti-Myc and anti-PEX14 antibodies (peroxisomal marker). Results are representative of three independent experiments. (b) Quantification of cells with peroxisomal protrusions. The average result of 3 independent experiments is shown, error bars indicate the mean +/- standard deviation. (a, b) Control cells occasionally contain peroxisomes with membrane protrusions (< 5 per cell; up to 5 µm in length). (c-e, b) Myc-Miro-PO induces the formation of peroxisomal membrane protrusions (> 5 per cell; > 5 µm in length). Results are representative of three independent experiments. (f-h, b) Silencing of PEX11β by siRNA significantly reduces the number of cells with peroxisomal membrane protrusions in controls and Myc-Miro-PO expressing cells. Results are representative of three independent experiments. Globular peroxisomes (arrows) with membrane protrusions (arrowheads) in (a) are highlighted. *** P < 0.001; ** P < 0.01 from a two-tailed unpaired t test; ns, not significant (p = 0.9695). Scale bars, 10 µm.