English: Developing dhkD null cells. dhkD- cells were grown on bacteria, harvested, and plated for development under standard conditions. Time-lapse was carried out using a Leica DM6000B microscope with a 5X objective. 3 to 5 percent of the developing cells were expressing GFP to enhance the ability to observe cell movement. The time-lapse sequence was begun once the developing cells showed signs of obvious mound formation and was continued past the “finger” stage. Pictures under fluorescent light were taken at 3-minute intervals. The movie is a 2.5-hour portion of the time-lapse sequence, beginning at the mound stage. The movie was compiled using 3 frames (9 minutes real time) per second.