A minimum of ten images per condition for each transfected and stained CEC line were taken for analysis purposes, using a confocal Zeiss 700 microscope. In the same way as previously described, CellProfiler software was used to identify and quantify MBNL1 puncta, defined in the Cy2 channel. The percentage of objects found in a nucleus after treatment with both ASOs was plotted individually, per cell line investigated (Figure S2).