Skip to main content
Advertisement
Browse Subject Areas
?

Click through the PLOS taxonomy to find articles in your field.

For more information about PLOS Subject Areas, click here.

< Back to Article

When the Genome Plays Dice: Circumvention of the Spindle Assembly Checkpoint and Near-Random Chromosome Segregation in Multipolar Cancer Cell Mitoses

Figure 3

Sister chromatid separation and spindle assembly checkpoint proteins.

FISH detection (A) of the chromosome 17 centromere (green) combined with immunofluorescence for beta tubulin (red) shows separation of the sister centromeres of one (arrow) but not of the other homologue (arrowhead). Immunofluorescence detection of separase (orange) and beta tubulin (green) shows localization of separase to spindle poles at metaphase (B) and early anaphase (C) and weak intensity staining in the midbody at telophase (D). Co-localisation of separase (red) and centrosomes (gamma tubulin in green) is observed at early bipolar anaphase (E, upper left) while several additional separase foci are present in an adjacent tetrapolar early anaphase cell (E, lower right). Co-labelling of separase (orange) and beta-tubulin (green) confirms this finding (F, tetrapolar at upper left and bipolar at lower right), and shows depletion of separase in a bipolar telophase cell (G, right) while several foci remain in a tetrapolar telophase cell (G, left). Immunofluorescence for CCNB1 (green) and AURKA (red) yields cytoplasmic staining in bipolar (H) and multipolar (J) metaphase cells while no staining is observed in bipolar (I) and multipolar (K) anaphase cells; AURKA stains the pericentrosomal regions at both metaphase and anaphase. Immunofluorescence for beta tubulin (green) and AURKB (red) shows localization of AURKB exclusively to centromeres at bipolar (L) and multipolar (M) metaphase, and exclusively to the spindle midzone at bipolar anaphase (N); in contrast, multipolar ana-telophase cells (O, P) exhibit AURKB in the midzone as well as on several chromosomes, indicating failure to separate the sister chromatids of some chromosomes (O, arrow). Immunofluorescence for beta tubulin (green) and MAD2L1 (red) shows MAD2L1 localization to centromeres at bipolar prometaphase (Q); at bipolar ana-telophase MAD2L1 foci is only present in chromosomes not incorporated in the mitotic process (R, arrow), whereas, at multipolar ana-telophase, multiple MAD2L1 foci are present on chromosomes (S).

Figure 3

doi: https://doi.org/10.1371/journal.pone.0001871.g003