Fig. 4

Functional Na⁺–Ca²⁺ exchange supports gene expression in cells with de-energised mitochondria. a LTC₄-induced c-fos gene transcription is reduced by FCCP but rescued following knockdown of mitofusin 2. Lower panel shows aggregate data from three independent experiments. U denotes untreated, F/O FCCP and oligomycin. F/O was applied 5 min prior to stimulation. LTC4/0Ca/La denotes the lack of c-fos response in the absence of Ca²⁺ influx, despite sustained cytosolic Ca²⁺ oscillations²⁵. b In mitofusin 2-deficient cells, rescue of LTC₄-induced c-fos transcription in the presence of mitochondrial depolarisation is prevented by either CGP-37157 (labelled CGP) or knockdown of the Na⁺–Ca²⁺ exchanger (NCX KD). c NFAT-dependent reporter gene expression is compared for the different conditions shown. The left-hand panel denotes wild-type cells and the right-hand panel responses after knockdown of mitofusin 2. Bar plot in the lower panel denotes aggregate data for the various conditions shown. FOV on y-axis is Field Of View. Here, FCCP and oligomycin were applied 5–10 min before stimulation with LTC₄. Agonist and FCCP/oligomycin were removed after a further 8 min. Scale bar denotes 10 μm. Error bars denote SEM