Immunocytochemistry employed standard techniques [32 (link), 33 (link)]. Secondary-antibody-only controls were performed by omitting primary antibodies during incubation (see Supplementary Data). Fluorescent imaging was performed on a Zeiss UV-LSM 510 META and a Nikon A1 confocal microscope. Sequential scanning of channels was performed to prevent false-positive co-localization. Images were quantified using ImageJ. Cell viability was assessed using a 3-(4,5-dimethylthiazol-2yl)-2,5 diphenyl tetra-zolium bromide (MTT) Cell Proliferation Assay Kit [34 (link)].