Association of mitochondria with spindle poles facilitates spindle alignment

Statistics of mitochondrial association with spindle poles in wild type and mto1∆ (Figures 1D and 2B) Out of the 35 imaged wild-type cells, 18 cells showed constant mitochondrial association (red bar in Figure 1D), 6 showed at least one spindle pole free from mitochondria for at least 5 minutes (green bar in Figure 1D), 6 displayed temporary mitochondrial detachment (not included in the comparison), and for 5 cells the association periods could not be determined accurately (not analyzed). The 6 free spindles were identified as free based on the observation that the distance between a spindle pole and the nearest mitochondrion was larger than ~200 nm. Out of the 22 imaged mto1∆ cells, 10 cells showed constant association with either a mitochondrial network or a small globular mitochondrion (red bar in Figure 2B), 9 showed at least one spindle pole free for at least 5 minutes (green bar in Figure 2B), and 3 displayed temporary association (not included in the comparison). Out of the 9 free spindles, 8 were identified as free based on the observation that the distance between a spindle pole and the nearest mitochondrion was larger than ~200 nm, and the remaining one based on the observation that the movements of the spindle and the adjacent mitochondria were uncorrelated.