FIGURE 8:

Localization of proteins in chemotaxing and dividing cortexillin-null cells. (A) Expressed GFP-myosin II and rhodamine-phalloidin–stained F-actin localize to the rear and front of chemotaxing ctxA⁻/B⁻ cells as in WT cells. (B) Rhodamine-phalloidin–stained F-actin illustrates the asymmetric division typical of many ctxA⁻B⁻ cells (top). Live imaging of GFP-myosin II expressed in ctxA⁻/B⁻ cells showing myosin II accumulates at the contractile ring in normal cytokinesis (middle; also see Supplemental Movie S9). F-Actin localizes in the two polar regions, and expressed GFP-myosin II concentrates at the cleavage furrow in ctxA⁻/B⁻ cells preceding cytokinesis completion (bottom). (C) Expressed GFP-CRAC and (D) expressed GFP-PI3K move to the front of WT and ctxA⁻/B⁻ cells, chemotaxing toward a cAMP-filled micropipette. Images recorded by time-lapse confocal microcopy. Scale bars, 5 μm.