Fig. 2. Kinetochore localisation of 53BP1 in mitosis. Prometaphase HeLa cells were immunostained doubly with anti-human-53BP1 and anti-centromeric antibodies (ACA) (a-d, 53BP1 in red, ACA in green), anti-CENP-B (i-l, 53BP1 in green, CENP-B in red), anti-CENP-E antibodies (m-p, 53BP1 in green, CENP-E in red). Prometaphase NIH3T3 cells were co-stained with anti-N-m53BP1 and ACA (e-h, m53BP1 in red, ACA in green). In a,e,i,m, DAPI staining is in blue. Human and mouse 53BP1 are detected as foci (c,g k,o) on the condensed mitotic chromatin (a,e,i,m) that are adjacent to the ACA and CENP-B dots (b,f,j). and partially overlap with the kinetochore protein CENP-E (panel n). Insets in b,f,j,n,o and p are magnified views of a kinetochores pairs (indicated with the arrow). Note that the cells are in natural mitosis without colcemid treatment. Images were recorded with a Delta Vision microscope.