WT and Mfn2 KO MEFs were co-transfected with plasmids encoding: mt-RFP and ER-Mfn2 or control (CT) plasmid. After 48 h, the cells were fixed. (D) Mitochondrial morphology was analysed (n=113-422 cells analyzed in 3 independent experiments) and (E) aspect ratio and (F) circularity calculated (n=360 mitochondria analyzed in 3 independent experiments). Data are presented as mean ± SEM. Data information: *p<0.05, one-way ANOVA followed by Tukey's post hoc test. Note that experiments were performed at the same time, so the values of WT and Mfn2 KO transfected with control plasmid are the same but the figures have been split in two for the sake of linearity. 