WT and Mfn2 KO MEFs were co-transfected with plasmids encoding: B) GFP and ERMITO-RLuc and ER-Mfn2 or control plasmid. After 24 h, the transfected cells were sorted and plated for another 24 h, after which RLuc was analyzed (n= 4 independent experiments). Data are presented as mean ± SEM. 