Chromosome positioning in quiescent interphase nuclei. Representative images displaying nuclei prepared for fluorescence in situ hybridization (2D-FISH), with whole-chromosome painting probes (green), and nuclear DNA is counterstained with 4',6-diamidino-2-phenylindole (DAPI) (blue). The cells were subjected to indirect immunofluorescence with anti-pKi-67 antibodies, and negative cells were selected. Cells were placed in low serum (0.5%) for 7 days, before fixation with methanol:acetic acid (3:1). The numbers (or letters) on the left side of each panel indicate the chromosome that has been hybridized. Scale bar = 10 μm.