Figure 2.

Robust control of perpendicular spindle orientation in epidermal basal cells. Wild-type cells expressing intrinsic ACD factors like mInsc localize mInsc/LGN/NuMA at the apical cortex in early mitosis but do not establish stable perpendicular spindle until late metaphase. As described in text, recent results have showed that spindle orientation can be regulated downstream of Insc/LGN recruitment by regulating NuMA maintenance at the apical end. Thus cells have mechanisms for robust regulation of mitotic spindle orientation to ensure optimum balance between SCD and ACD. Such mechanisms might help to respond quickly to extrinsic cues or intrinsic imbalances.