FIGURE 10:

Use of our optogenetic system to establish the spatial requirements of Clb2–Cdk1 activity in budding yeast. (A) The system is capable of recruiting PIF-mCitrine to only one spindle pole body by restricting the activating light to the daughter. (B) Whereas illuminating both mother and daughter with 650-nm light stabilizes the spindle at the end of mitosis, restricting Clb2 recruitment to either the mother SPB or daughter SPB is not sufficient to stabilize the spindle. Green channel represents the SPB (Spc42-GFP). To control for day-to-day variations in doubling time due to ambient temperature in the microscope room and timing of movie since yeast dilution, experimental (650-nm illuminated) cells were compared with control cells (no 650-nm illumination) in the same microscope field of view.