Fig. 1. Unclustered kinetochore pairs are efficiently retrieved to the spindle pole before sister chromatid bi-orientation. (A) ndc80-gfp cdc11-cfp and mto1 ndc80-gfp cdc11-cfp cells were fixed and stained with DAPI to reveal the position of kinetochores (green), spindle poles (red) and chromatin (blue). (B) The frequency by which unclustered kinetochores appear in mto1 ndc80-gfp cdc11-cfp cells when the nucleus is placed in the middle of the cell (region A), displaced to one side of the cell but not at the cell tip (region B) or at the cell tip (region C) was calculated. (C) Images from a movie of mto1 ndc80-gfp cdc11-cfp cells in mitosis. Spindle poles are shown in red and kinetochores are shown in green. Note that an unclustered pair of sister chromatids (white arrowhead) are drawn back to the spindle pole and then bi-oriented on the mitotic spindle. Bar, 1 µm. (D) The distance between the unclustered kinetochore pair and the spindle pole was calculated at 30-second intervals in multiple movies of ndc80-gfp cdc11-cfp cells.