Figure 3.

MCU forms oligomers in vitro and in vivo. (A) Co-immunoprecipitation experiments. HeLa cells were transfected with the indicated constructs. HA-tagged MCU was immunoprecipitated from cell extracts with a specific α-HA antibody. The precipitated proteins were immunoblotted with α-HA and α-GFP antibodies. (B) Emission spectra analysis of HeLa cells transfected with MCU-GFP or MCU-GFP and MCU-mCherry and analysed after 24 h. (C) FRET analysis. HeLa cells were transfected with GFP and mCherry or MCU-GFP and MCU-mCherry and analysed after 24 h. Images of donor and acceptor were taken before and after photobleaching the indicated region (white box). FRET was calculated as detailed in Materials and methods. Histogram bar diagram shows FRET efficiency of the indicated donor and acceptor pairs. Descriptive statistics can be found in Supplementary Table S1.