Fig. 4.
Complementation of Ddcar1car3 by DmcAR. (A) Restoration of development. The D. discoideum car1car3 mutant, its parent DH1, and car1car3 transformed with A15:DmcAR were incubated on nonnutrient agar at 22°C and photographed at 2-h intervals. (Bar, 100 μm.) (B) Oscillatory signaling. car1car3/A15:DmcAR cells were incubated for 5 h at 4 × 105 cells per cm2 on agar and subsequently tracked during 50 min at 10-s intervals by time-lapse videomicroscopy under phase-contrast illumination. Optical density waves were enhanced by image subtraction (30). The 256th video frame is shown. (Bar, 100 μm.) See Movie 1, which is published as supporting information on the PNAS web site.