Fig. 1

CGGBP1 and CTCF colocalize in the nucleus. a Human juvenile fibroblasts were co-immunostained for CGGBP1 (green) and CTCF (red). Nuclei were counterstained with DAPI (blue). b Zoomed view of a representative nucleus (630× zoom, focal plane thickness 0.896 micrometers) shows some overlap between signals for DAPI, CGGBP1 and CTCF. c Blocking was done with anti-CGGBP1 rabbit polyclonal antibody followed by incubation with detection antibody (anti-CGGBP1 rabbit polyclonal antibody and anti-CTCF mouse monoclonal antibody). d Blocking was done with anti-CTCF mouse monoclonal antibody followed by incubation with detection antibody (anti-CGGBP1 rabbit polyclonal antibody and anti-CTCF mouse monoclonal antibody). Micrographs show signal for DAPI (blue), CGGBP1 (green) and CTCF (red). e PLA (red foci) shows the proximity between CTCF and CGGBP1 in situ. Nuclei were stained with DAPI (blue). CGGBP1–CTCF proximity was stronger in the nuclei than cytoplasm (inset of rabbit anti-CGGBP1:mouse anti-CTCF sample). No significant PLA signal was observed in IgG and negative controls with no-primary antibody (inset of no-primary antibody sample). f Counting of PLA signals shows proximity detected using specific antibodies as significantly higher than the negative controls. Also the PLA signal frequency in the nuclei (blue) was higher than in the cytoplasm (green). All images were captured with confocal planes of 1.601 µm