Figure 4. Improper anchoring of astral microtubules at cell cortex as a source of spindle geometry defects.
In cells with normal spindle geometry (left), dynein/dynactin interacts with the Gαi-LGN-NuMA anchor protein complex [89] and captures astral microtubules near the cortex contributing to symmetrical spindle pole orientation and proper kinetochore-microtubule attachment. In cells with abnormal spindle geometry, demarcation of cortical anchoring regions is not symmetrical, resulting in improper kinetochore-microtubule attachment (right).