Fig. 12. Mistargeting of CENP-A to the inactive centromere of dicentric chromosomes is not sufficient for kinetochore formation. CENP-A was overexpressed for 48 hours in a cell line (COLO 320DM) carrying multiple dicentric chromosomes and was immunolocalized using SH-CREST autoimmune serum. Cells were arrested in mitosis with Colcemid and harvested by mitotic shake-off. In untransfected control cells, CENP-A is only observed at active and not inactive centromeres (not shown). In cells overexpressing the protein, CENP-A was observed along the lengths of chromosome arms and at inactive centromeres. Despite the mistargeting of CENP-A, anti-ZW10 antibody localized only at the active centromere (arrow) and not at the inactive centromere (arrowhead) of dicentric chromosomes. DNA was counterstained with DAPI. Bar, 10 µm.