Possible scenarios in which centrosome centering (a) and spindle elongation (b) set the upper and lower limit of cell size. (a) If the cell exceeds the upper limit of size, the centrosome, and consequently the mitotic spindle, cannot position at the cell center, leading to nonsymmetrical cell division (middle panels versus left panels). If the cell falls below the lower limit, the centrosome may not stably position at the cell center due to the excess elastic forces of the microtubules (right panels versus left panels). (b) If the cell exceeds the upper limit, astral microtubules do not reach the cell cortex, potentially leading to insufficient spindle elongation. If the cell falls below the lower limit, there may not be sufficient space for accurate chromosome segregation compared to the size of the cell's chromosomes.
Marshall et al. BMC Biology 2012 10:101 doi:10.1186/1741-7007-10-101