Fig. 5: The force imbalance causes kinetochore declustering and triggers the SAC.
a, Maximum growth rates of fused-chromosome strains with and without MAD2 deletion. Boxes represent means and s.d. Means were compared using a two-tailed Student’s t-test (from left to right, n = 14, 13, 15 and 16 independent population measurements). b, The time from SPB doubling to max. anaphase separation. Boxes represent the means and s.d. Means were compared using a two-tailed Student’s t-test (from left to right, n = 17, 14, 15 and 13 independent single-cell measurements). c, Maximum growth rates of fused-chromosome strains with and without MAD2 deletion + benomyl treatment (55 µM). Boxes represent means and s.d. Means were compared using a two-tailed Student’s t-test (from left to right, n = 15, 15, 14 and 13 independent population measurements). d, Western blot analysis of Pds1 levels after G1 release for 16- and 3-chromosome strains. Cells were collected at the indicated time points and alpha-factor pheromone was added again 45 min after release to prevent the cells from entering a second cell cycle. Actin levels were used as a loading control. Pds1-normalized values are shown in the bar plot at the bottom. An independent repeat of this experiment with analysis of the second cell cycle can be found in Extended Data Fig. 5f. e, Proportion of cells with a bi-lobed kinetochore signal (bi-modal Ndc80 signal along the spindle pole to spindle pole axis) in both metaphase and anaphase. Proportions were compared using a two-proportions z-test (from left to right, n = 26, 56, 100, 24, 41 and 31 independent single-cell measurements). f, Montage of kinetochore (Ndc80-mNG) and SPB (Spc42-mCherry) dynamics during metaphase for 16- and 3-chromosome strains. Scale bar, 2 µm; intervals are 30 s. g, Montage of kinetochore (Ndc80-mNG) and SPB (Spc42-mCherry) dynamics during metaphase in three-chromosome strains with benomyl (55 µM). Scale bar, 2 µm; intervals are 1 min. Source numerical data and unprocessed blots are available in source data.
