Fig. 4

Effect of Mfn2 knockdown and mutant PS2 on ER–mitochondria interface. Immunofluorescence against mitochondria (Tom20, red) is shown in the panels on the middle. The green channel is the merge of several planes. Scale bar 20 µm. a Representative confocal pictures of HeLa cells expressing the SPLICS_S probe. b Quantification of SPLICS_S contacts by 3D rendering of complete z-stacks. Mean ± SEM: SCR shRNA 70 ± 4, n = 76 cells; shRNA Mfn2 #1 98 ± 7, n = 26 cells; shRNA Mfn2 #3 108 ± 7, n = 28 cells; shRNA Mfn2 #4: 95 ± 7, n = 23 cells. c Representative confocal pictures of HeLa cells expressing the SPLICS_L probe. d Quantification of SPLICS_L contacts by 3D rendering of complete z-stacks. Mean ± SEM: SCR shRNA 238 ± 10, n = 30 cells; shRNA Mfn2 #1 172 ± 9, n = 27 cells; shRNA Mfn2 #3 176 ± 8, n = 29 cells; shRNA Mfn2 #4 190 ± 10, n = 27 cells. e Representative confocal pictures of human fibroblasts from a patient with the N141I mutation in PS2 (bottom panel) and an age-matched control (upper panel) expressing the SPLICS_S probe. The green channel is the merge of several planes. Scale bar 20 µm. f Quantification of ER–mitochondria short contacts by 3D rendering of complete z-stacks. Mean ± SEM: CTRL 50 ± 5, n = 20 cells; PS2-N14I: 101 ± 12, n = 21 cells. Data shown are the result of 2–5 independent experiments. **p ≤ 0.01, ***p ≤ 0.001, ****p ≤ 0.0001.